Sound Practices Mailing List Files - Volume 2
=========================================================================
From: "Daniel J. Marshall" <danmarshall@worldnet.att.net>
Subject: [JN] FA: Accuphase P-300 Power Amplifier
Date: Fri, 04 Feb 2000 08:25:13 -0800
Source: Sound Digest Archive v02.n433
Hi All,
Not needing 150 watts/channel, I decided to sell the Accuphase amp. It
sold on ebay for $500 several days ago, but the buyer pussed-out and
refused to complete the transaction, said it was too large to fit into
his cabinetry, so it was relisted. I intended to put in a reserve price
of $450, but somehow, in the listing it was neglected. The bid is
currently $360 and the auction closes in a couple hours at 10:48 West
Coast time. As SS amps go, Accuphase is an excellent amplifier. To my
ear, I can't hear much difference between it and the W-5M Heath tube
amps I just tweaked in. I tried to measure the distortion, but it was
down below that of the HP 200CD low-distortion test oscillator, at any
power level. I could observe no crossover distortion that SS amps are
often criticized for, even at a hundred milliwats output. One collector
who has Krell, Threshold, Mac, etc. claims that his Accuphase amps sound
better than anything else he has. Anyway, it is an excellent amp in very
nice condition. If you have low to medium efficiency speakers you would
be very pleased with it. New Accuphase amps sell in the $6,000 to
$9,000 range, or thereabouts.
http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=251132986
Thanx.
Dan Marshall
=========================================================================
From: "Daniel J. Marshall" <danmarshall@worldnet.att.net>
Subject: [JN] FA: Allen 75s, Quad NOS 2A3s, Jensen A-12
Date: Fri, 10 Mar 2000 09:41:05 -0800
Source: Sound Digest Archive v02.n478
Hi All,
I have listed the three items above on eBay. Here is the seller's list,
in case anyone is interested in having a look. All are in excellent
condition.
http://cgi6.ebay.com/aw-cgi/eBayISAPI.dll?ViewListedItems&userid=danmarshall@worldnet.att.net
DM
=========================================================================
From: Dan Marshall <mdaniel7@uswest.net>
Subject: [JN] FA: Allen 90 Watt Tube Amps
Date: Mon, 17 Sep 2001 13:02:35 +0000
Source: Sound Digest Archive v02.n977
Hi All,
I have a nice pair of largish Allen Organ tube amps for sale. They have
been checked out and are in good operating condition. So, far I have
not had success with them on eBay, though, based upon bids on previous
Allen 90 amp listings, it would seem that they are bargain priced.
The terrorist activity has seemingly put a damper on many things,
including eBay activity, or so it seems, so perhaps this is the reason.
Anyway, if you have need of a pair of quality, hefty tube amps, please
check these out.
The output iron seems to be particularly good, quite possibly Peerless,
though I have no proof of this. They are sufficiently wideband that no
compensating cap is used across the feedback resistor, which I have not
seen before, nor is there other freq compensation in the amps. I have a
detailed rundown on them in the listing.
http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=1275862151
Sorry about the commercialization, but I need to raise some short term
cash.
Dan Marshall
=========================================================================
From: analogtubeaudio@t-online.de (Robert Graetke)
Subject: [JN] ***FA: audio transformer Western Electric KS 8728
Date: Sun, 20 Feb 2000 09:28:56 +0100
Source: Sound Digest Archive v02.n455
http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=264571705
=========================================================================
From: analogtubeaudio@t-online.de (Robert Graetke)
Subject: [JN] ***FA: audio transformer Western Electric KS 8728
Date: Sun, 20 Feb 2000 09:31:04 +0100
Source: Sound Digest Archive v02.n455
http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=264571705
=========================================================================
From: Jeremy Epstein <jepstein@shwd.com>
Subject: [JN] Fabulous Offer Is CLOSED
Date: Tue, 15 Jun 1999 09:28:44 -0400
Source: Sound Digest Archive v02.n179
Thanks to the speedy Joe who replied!
- -j
- --
=====================================
Jeremy Epstein .... jepstein@shwd.com
=====================================
=========================================================================
From: RonSonic <rbales@gte.net>
Subject: [JN] FA: DeccaCartridge and EV SP12B's
Date: Mon, 30 Oct 2000 18:41:07 -0500
Source: Sound Digest Archive v02.n711
Tasty additions to the beginning and end of the signal chain.
EV SP12B 12" full range drivers
http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=481163422
Decca Phono Cartridge
http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=481181368
Thanks for the spamwidth.
Ron
Check out the band at http://www.flapcats.com
Always new songs online at
http://artists.mp3s.com/artists/122/flapcats.html
=========================================================================
From: "Cameron Brook" <cambrook@cyllene.uwa.edu.au>
Subject: [JN] FA: Fisher remote control
Date: Sat, 13 Jan 2001 19:15:19 +0800
Source: Sound Digest Archive v02.n783
This may be of interest to some Joes.
http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=1206611492
I have no connection etc etc, I just found this while browsing
Cameron
=========================================================================
From: Dan Marshall <mdaniel7@uswest.net>
Subject: [JN] FA/FS
Date: Thu, 29 Mar 2001 15:57:55 +0000
Source: Sound Digest Archive v02.n848
Hi All,
My life is at a turning point (for the better), consequently, I intend
to sell most of the stuff I have accumulated over the years, mainly
amps, speakers, speaker components, a few SS pieces, etc. I just listed
some stuff on eBay, all good stuff, output transformers, speakers, a
vintage amp, etc. Have a look if interested. I will be selling more
stuff as I get around to checking it out and either getting it listed,
or perhaps offering it here.
http://cgi6.ebay.com/aw-cgi/eBayISAPI.dll?ViewListedItems&userid=danmarshall&include=0&since=-1&sort
=2&rows=25
Dan Marshall
=========================================================================
From: Rick Francis <rfrancis@glasscity.net>
Subject: [JN] FA/FS/FT: WE and other tubes
Date: Mon, 25 Jan 1999 15:52:03 -0500
Source: Sound Digest Archive v02.n012
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I'm selling some WE and other tubes on <shudder> e-bay. Even if you think buying
on e-bay is for suckers, you might take a look at the pretty pictures I took with
my new digital camera. I have duplicates of many of these tubes (okay, not the
Gold Lion KT-66), esp. the WE tubes. So if you see something you like, e-mail me
and maybe we can work it out. Some WE auctions end today, but see pics at
> http://www.glasscity.net/users/rfrancis/WE387A-1.jpg
>
> http://www.glasscity.net/users/rfrancis/WE387A-2.jpg
>
My current auctions:
http://cgi3.ebay.com/aw-cgi/eBayISAPI.dll?ViewListedItems&userid=rfrancis@glasscity.net
Rick
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<HTML>
I'm selling some WE and other tubes on <shudder> e-bay. Even if
you think buying on e-bay is for suckers, you might take a look at the
pretty pictures I took with my new digital camera. I have duplicates
of many of these tubes (okay, not the Gold Lion KT-66), esp. the WE tubes.
So if you see something you like, e-mail me and maybe we can work it out.
Some WE auctions end today, but see pics at
<BLOCKQUOTE TYPE=CITE>
<PRE><A HREF="http://www.glasscity.net/users/rfrancis/WE387A-1.jpg">http://www.glasscity.net/users/r
francis/WE387A-1.jpg</A></PRE>
</BLOCKQUOTE>
<BLOCKQUOTE TYPE=CITE>
<PRE><A HREF="http://www.glasscity.net/users/rfrancis/WE387A-2.jpg">http://www.glasscity.net/users/r
francis/WE387A-2.jpg</A></PRE>
</BLOCKQUOTE>
My current auctions:
<BR><A HREF="http://cgi3.ebay.com/aw-cgi/eBayISAPI.dll?ViewListedItems">http://cgi3.ebay.com/aw-cgi/
eBayISAPI.dll?ViewListedItems</A>&userid=rfrancis@glasscity.net
<P>Rick
<BR>
<BR> </HTML>
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=========================================================================
From: Steve Van Osdell <svanos@queencity.com>
Subject: [JN] FA: Goodman Audiom 955 Woofers
Date: Wed, 09 Aug 2000 23:59:40 -0400
Source: Sound Digest Archive v02.n623
If anyone is interested, I've got a pair of Goodman Adiom 955 Woofers
(FS=25) up for auction on ebay.
Thanks, Steve
=========================================================================
From: "Aaron Bohnen" <bohnen@unixg.ubc.ca>
Subject: [JN] FA: Goodmans Audiom 81 15" alnico woofer
Date: Mon, 8 Nov 1999 11:12:00 -0800
Source: Sound Digest Archive v02.n325
Hi everyone,
I'm really putting in a big effort to clean out a few things from my
burgeoning audio collection. I'm auctioning a Goodmans Audiom 81 16 Ohm
15" woofer on Ebay right now. If anyone is interested please have a look
at:
http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=195690774
Thanks for the space and best regards to all,
Aaron
___________________________________________________________
Aaron Bohnen email: bohnen@unixg.ubc.ca
- -Ph.D. Student, Civil Engineering Department, U.B.C.
- -website: http://www.civil.ubc.ca/home/bohnen
=========================================================================
From: "R. Thatcher" <rht3@alumni.cwru.edu>
Subject: [JN] FA: Goodmans Axiom 100 Mk2
Date: Wed, 23 Aug 2000 09:12:36 -0400
Source: Sound Digest Archive v02.n639
Sorry for the bandwidth...
http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=416496178
Does anyone have a Mullard 6DJ8 in good condition they'd part with?
Used is fine, but the microphonics on mine are getting worse and worse!
Randy
=========================================================================
From: "Daniel J. Marshall" <danmarshall@worldnet.att.net>
Subject: [JN] FA: Good Stuff
Date: Fri, 24 Mar 2000 12:47:10 -0800
Source: Sound Digest Archive v02.n494
Hi All,
I posted a bunch of stuff on eBay yesterday (closing Sunday), some
pretty neat stuff, some not so neat. It was just too much stuff to get
involved in multiple emails and determining who was first etc., so I
pussed-out and listed it on eBay. There will be more to come, when I
get around to listing it. There are 288C drivers, UTC interstage and
linestage trannies, big UTC chokes, tweeters, midranges, woofers, a NOS
JBL 075 diaphram and a very nice, good-sized isolation transformer with
plugs, circuit breaker, on/off, etc.
http://cgi3.ebay.com/aw-cgi/eBayISAPI.dll?ViewListedItems&userid=danmarshall@worldnet.att.net
Anyway, if interested, have a looksee.
Dan Marshall
=========================================================================
From: TubeGarden@aol.com
Subject: [JN] Faith, Hope and Glory (rantlette)
Date: Thu, 11 Jan 2001 19:52:47 EST
Source: Sound Digest Archive v02.n782
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In a message dated 1/11/01 12:40:47 PM US Mountain Standard Time,
bart.s@bigpond.net.au writes:
> As soon as we take this path we are no longer engineers attempting to design
> the "faithful amplifier" but musical artists painting with a pallet of
> assorted electronics. What is wrong with recognizing this?? Come out of the
> closet!
>
Greets!
Engineers, unlike us rabid audio geeks :), are trained professionals hired to
do a job. They fulfill the requirements set for them by management.
After the cost/specification goals are achieved, or acceptable excuses agreed
to, the marketing department starts grinding out collateral with incredible
bullshit phrases like 'makes every camper a concert hall', 'faithful to every
musical nuance', even 'perfect sound forever'.
Engineering is just honest work, not the moral high ground.
I enjoy listening to circuits built to explore an idea. I am retired and
unencumbered by management trying to execute a business plan. Many decades in
the trenches, er, staff meetings, under the direction of intellectual black
hole calendar worshippers have brought me out into the sunny beaches of
research and delight.
Engineering without management is like sex without guilt.
I am still an engineer, but, now I work to hear more, with less effort, not
add 'features' to room ornaments :)
Happy Ears!
Al B^}
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<HTML><FONT FACE=arial,helvetica><BODY BGCOLOR="#ffffff"><FONT SIZE=2>In a message dated 1/11/01 12
:40:47 PM US Mountain Standard Time, <BR>bart.s@bigpond.net.au writes:
<BR>
<BR>
<BR><BLOCKQUOTE TYPE=CITE style="BORDER-LEFT: #0000ff 2px solid; MARGIN-LEFT: 5px; MARGIN-RIGHT: 0px
; PADDING-LEFT: 5px">As soon as we take this path we are no longer engineers attempting to design
<BR>the "faithful amplifier" but musical artists painting with a pallet of
<BR>assorted electronics. What is wrong with recognizing this?? Come out of the
<BR>closet!
<BR></BLOCKQUOTE>
<BR>
<BR>Greets!
<BR>
<BR>Engineers, unlike us rabid audio geeks :), are trained professionals hired to <BR>do a job. They
fulfill the requirements set for them by management.
<BR>
<BR>After the cost/specification goals are achieved, or acceptable excuses agreed <BR>to, the market
ing department starts grinding out collateral with incredible <BR>bullshit phrases like 'makes every
camper a concert hall', 'faithful to every <BR>musical nuance', even 'perfect sound forever'.
<BR>
<BR>Engineering is just honest work, not the moral high ground.
<BR>
<BR>I enjoy listening to circuits built to explore an idea. I am retired and <BR>unencumbered by man
agement trying to execute a business plan. Many decades in <BR>the trenches, er, staff meetings, und
er the direction of intellectual black <BR>hole calendar worshippers have brought me out into the su
nny beaches of <BR>research and delight.
<BR>
<BR>Engineering without management is like sex without guilt.
<BR>
<BR>I am still an engineer, but, now I work to hear more, with less effort, not <BR>add 'features' t
o room ornaments :)
<BR>
<BR>Happy Ears!
<BR>Al B^}
<BR>
<BR></FONT></HTML>
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=========================================================================
From: "Larry D. Moore" <l-moore@onu.edu>
Subject: Re: [JN] Faith, Hope and Glory (rantlette)
Date: Fri, 12 Jan 2001 07:53:02 -0500
Source: Sound Digest Archive v02.n782
At 07:52 PM 1/11/01 EST, you wrote:
>In a message dated 1/11/01 12:40:47 PM US Mountain Standard Time,
>bart.s@bigpond.net.au writes:
>
>
>As soon as we take this path we are no longer engineers attempting to design
>the "faithful amplifier" but musical artists painting with a pallet of
>assorted electronics. What is wrong with recognizing this?? Come out of the
>closet!
>
>
>
>Greets!
>
>Engineers, unlike us rabid audio geeks :), are trained professionals hired
to
>do a job. They fulfill the requirements set for them by management.
I think they try to define what it is that it possible for management to do
as well. Having said that, I think the two generally have something
different in mind as to what requirements are achievable.
>After the cost/specification goals are achieved, or acceptable excuses
agreed
>to, the marketing department starts grinding out collateral with incredible
>bullshit phrases like 'makes every camper a concert hall', 'faithful to
every
>musical nuance', even 'perfect sound forever'.
Or try to figure out the short sightedness of the project managers....What
I mean by this is that there is almost a relentlesss request for cost
reduction in an engineering setting. Probably the higher the technology,
the more this is so...
>Engineering is just honest work, not the moral high ground.
I disagree. I think that there are also moral decisions involved.
Engineers are capable of determining what is in the best interest of the
comsumer just like anyone else. Also, engineers are capable of seeing
ideas that project managers are not capable of. Call them features if you
like. Trouble is once the enigneer devulges the idea, then his or her life
gets difficult because then you are in a position where you have to
produce....
>I enjoy listening to circuits built to explore an idea.
Me too.
> I am retired and
>unencumbered by management trying to execute a business plan. Many decades
in
>the trenches, er, staff meetings, under the direction of intellectual black
>hole calendar worshippers have brought me out into the sunny beaches of
>research and delight.
I'm just speaking from the cellular RF industry when I worked for AT&T,
Lucent and Bell Labs. I was a designer. The pressure was on. Less cost,
more profit. Greater ability to sell.
>Engineering without management is like sex without guilt.
Engineering is like sex without a condom. You doing it, but you don't feel
it as much. Art is sex without a condom. You get it all, including laying
your emotions and personality on the line.
>I am still an engineer, but, now I work to hear more, with less effort, not
>add 'features' to room ornaments :)
I still an engineer too; but, I went to law school so that I would have
more control over my life and there was more passion in what I do.
>Happy Ears!
> B^}
Great post. I'm with ya!
=========================================================================
From: "Larry D. Moore" <l-moore@onu.edu>
Subject: Re: [JN] Faith, Hope and Glory (rantlette)
Date: Fri, 12 Jan 2001 09:52:18 -0500
Source: Sound Digest Archive v02.n782
At 02:38 PM 1/12/01 +0100, Christian Rintelen wrote:
>
>"Larry D. Moore" wrote:
>
>> >Engineering is just honest work, not the moral high ground.
>>
>> I disagree. I think that there are also moral decisions involved.
>
>Aren't you confusing moral and ethics?
Nah. They are too intertwined.
>> Engineers are capable of determining what is in the best interest of the
>> comsumer just like anyone else.
>
>I find this statement slightly arrogant because of it's aspect "I'm an
engineer
>*and* a consumer as well, therefore what's good for me is good for everybody
>else".
Never said I was a consumer. The things that I've designed, I've never
bought. My point is: I've been in a position where the "management" has
wanted to take a "feature" out and I've refused to do it. Take 911 service
triangulation services for location availablity offerings in a cellular
community for example.
> I'm not an engineer, but still I believe (wrongfully maybe ;-) that I
>alone can decide what's in the best interest of a consumer like me...
>
>Christian
I think you missed my point. It is: Engineer's opinions are like everyone
else's. Yours, mine, and any other joe-blow. They all count. Perhaps
what you're unhappy with is that other people make decisions for us all
everyday. Take the government for example. Here, we are saying the same
thing. I like it no more than you. Believe me. However, it is there none
the less.
=========================================================================
From: Christian Rintelen <christian@rintelen.ch>
Subject: Re: [JN] Faith, Hope and Glory (rantlette)
Date: Fri, 12 Jan 2001 14:38:57 +0100
Source: Sound Digest Archive v02.n782
"Larry D. Moore" wrote:
> >Engineering is just honest work, not the moral high ground.
>
> I disagree. I think that there are also moral decisions involved.
Aren't you confusing moral and ethics?
> Engineers are capable of determining what is in the best interest of the
> comsumer just like anyone else.
I find this statement slightly arrogant because of it's aspect "I'm an engineer
*and* a consumer as well, therefore what's good for me is good for everybody
else". I'm not an engineer, but still I believe (wrongfully maybe ;-) that I
alone can decide what's in the best interest of a consumer like me...
Christian
=========================================================================
From: "Bart Shepherd \(Home\)" <bart.s@bigpond.net.au>
Subject: RE: [JN] Faith, Hope and Glory (rantlette)
Date: Fri, 12 Jan 2001 19:41:48 +1100
Source: Sound Digest Archive v02.n782
This is a multi-part message in MIME format.
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[>
Engineering is just honest work, not the moral high ground.
>
Hi there,
no high moral ground here ;-)
The "engineer" definition I like best is:
"the guy who can do for $10 what any idiot can do for $100"
Example cute trick - the Fisher idea of making the output tubes' common
cathode bias resistor out of prior stage filaments in series, hence
providing a DC filament supply for free and maybe a tiny bit of feedback and
hum cancellation.
Not sure exactly how well this works in practice but it sure looks cute on
the schematic!
Bart
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charset="US-ASCII"
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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML><HEAD>
<META content=3D"text/html; charset=3Dus-ascii" =
http-equiv=3DContent-Type>
<META content=3D"MSHTML 5.00.2920.0" name=3DGENERATOR></HEAD>
<BODY bgColor=3D#ffffff>
<BLOCKQUOTE>
<DIV align=3Dleft class=3DOutlookMessageHeader dir=3Dltr><FONT =
face=3DTahoma></DIV>
<DIV></FONT><FONT face=3DArial><FONT size=3D2><SPAN =
class=3D924403208-12012001><FONT=20
color=3D#0000ff>[> </FONT></SPAN><BR>Engineering is just =
honest work,=20
not the moral high ground. <BR><FONT color=3D#0000ff></FONT><FONT =
size=3D2><SPAN=20
=
class=3D924403208-12012001>> </SPAN></FONT></FONT></FONT></DIV>
<DIV><FONT face=3DArial><FONT color=3D#0000ff><FONT size=3D2><SPAN=20
class=3D924403208-12012001></SPAN></FONT></FONT></FONT> </DIV>
<DIV><SPAN class=3D924403208-12012001></SPAN><FONT size=3D2><FONT=20
color=3D#0000ff><FONT face=3DArial><SPAN class=3D924403208-12012001>Hi =
there,</SPAN></FONT></FONT></FONT></DIV>
<DIV><FONT size=3D2><FONT color=3D#0000ff><FONT face=3DArial><SPAN=20
class=3D924403208-12012001></SPAN></FONT></FONT></FONT> </DIV>
<DIV><SPAN class=3D924403208-12012001></SPAN><FONT size=3D2><FONT=20
color=3D#0000ff><FONT face=3DArial><SPAN class=3D924403208-12012001>no =
high moral=20
ground here ;-)</SPAN></FONT></FONT></FONT></DIV>
<DIV><FONT size=3D2><FONT color=3D#0000ff><FONT face=3DArial><SPAN=20
class=3D924403208-12012001></SPAN></FONT></FONT></FONT> </DIV>
<DIV><SPAN class=3D924403208-12012001></SPAN><FONT size=3D2><FONT=20
color=3D#0000ff><FONT face=3DArial><SPAN =
class=3D924403208-12012001>The "engineer"=20
definition I like best is:</SPAN></FONT></FONT></FONT></DIV>
<DIV><FONT size=3D2><FONT color=3D#0000ff><FONT face=3DArial><SPAN=20
class=3D924403208-12012001></SPAN></FONT></FONT></FONT> </DIV>
<DIV><SPAN class=3D924403208-12012001></SPAN><FONT size=3D2><FONT=20
color=3D#0000ff><FONT face=3DArial><SPAN =
class=3D924403208-12012001>"the guy who can=20
do for $10 what any idiot can do for =
$100"</SPAN></FONT></FONT></FONT></DIV>
<DIV><FONT size=3D2><FONT color=3D#0000ff><FONT face=3DArial><SPAN=20
class=3D924403208-12012001></SPAN></FONT></FONT></FONT> </DIV>
<DIV><FONT size=3D2><FONT color=3D#0000ff><FONT face=3DArial><SPAN=20
class=3D924403208-12012001>Example cute trick - the Fisher idea of =
making the=20
output tubes' common cathode bias resistor out of prior stage =
filaments=20
in series, hence providing a DC filament supply for free and maybe a =
tiny bit=20
of feedback and hum cancellation.</SPAN></FONT></FONT></FONT></DIV>
<DIV><FONT size=3D2><FONT color=3D#0000ff><FONT face=3DArial><SPAN=20
class=3D924403208-12012001></SPAN></FONT></FONT></FONT> </DIV>
<DIV><FONT size=3D2><FONT color=3D#0000ff><FONT face=3DArial><SPAN=20
class=3D924403208-12012001>Not sure exactly how well this works in =
practice but=20
it sure looks cute on the schematic!</SPAN></FONT></FONT></FONT></DIV>
<DIV><FONT size=3D2><FONT color=3D#0000ff><FONT face=3DArial><SPAN=20
class=3D924403208-12012001></SPAN></FONT></FONT></FONT> </DIV>
<DIV><FONT size=3D2><FONT color=3D#0000ff><FONT face=3DArial><SPAN=20
class=3D924403208-12012001>Bart</SPAN></FONT></FONT></FONT></DIV>
<DIV><FONT size=3D2><FONT color=3D#0000ff><FONT face=3DArial><SPAN=20
class=3D924403208-12012001></SPAN></FONT></FONT></FONT> </DIV>
<DIV><FONT size=3D2><FONT color=3D#0000ff><FONT face=3DArial><SPAN=20
class=3D924403208-12012001></SPAN></FONT></FONT></FONT> </DIV>
<DIV><FONT size=3D2><FONT color=3D#0000ff><FONT face=3DArial><SPAN=20
=
class=3D924403208-12012001></SPAN><BR><BR> </DIV></FONT></FONT></FON=
T></BLOCKQUOTE></BODY></HTML>
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=========================================================================
From: "Sellek, Grant (TSA)" <Grant.Sellek@transport.sa.gov.au>
Subject: RE: [JN] Faith, Hope and Glory (rantlette)
Date: Sat, 13 Jan 2001 07:22:24 +1030
Source: Sound Digest Archive v02.n783
>-----Original Message-----
>From: Christian Rintelen [mailto:christian@rintelen.ch]
>Sent: Saturday, 13 January 2001
>
> I'm not an engineer, but still I believe (wrongfully
>maybe ;-) that I
>alone can decide what's in the best interest of a consumer like me...
Far from it. Most consumers will buy whatever's cheapest and look OK,
and don't have a clue about safety and functionality. The latter they
often learn about soon after purchase, or gradually; but safety
remains hidden from their awareness/concern, unless they are unlucky.
Grant Sellek, Adelaide, Australia
=========================================================================
From: "Aaron Bohnen" <bohnen@unixg.ubc.ca>
Subject: [JN] FA: JBL LE8T full-range drivers with PR8 passive radiators
Date: Mon, 25 Oct 1999 12:06:31 -0700
Source: Sound Digest Archive v02.n314
Hi everyone,
I have a pair of JBL LE8T alnico full-range 8" drivers with matching PR8
passive radiators up on Ebay right now. They sound and work great, have
recently had new surrounds installed, etc. etc. Efficiency is a little
low at 89~90 dB/1Wm for really flea-power amps but maybe reasonable for
the 8+ wpc crowd.
Anyway, if interested have a look at:
http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=186383120
they're currently $US 212.50 - if they don't get bid up any higher that
will be a pretty good deal for someone.
best regards to all and humble apologies for wasting bandwidth on this -
I hope it isn't wasted bandwidth. I really like these and I'd like to see
these go to a Joe rather than off to a stranger.
best regards,
Aaron
___________________________________________________________
Aaron Bohnen email: bohnen@unixg.ubc.ca
- -Ph.D. Student, Civil Engineering Department, U.B.C.
- -website: http://www.civil.ubc.ca/home/bohnen
=========================================================================
From: TubeGarden@aol.com
Subject: Re: [JN] Fake Orgasms -- Let's not give anyone the "audio daffy"
Date: Thu, 11 Oct 2001 15:16:13 EDT
Source: Sound Digest Archive v02.n992
- --part1_14b.25b220a.28f749fd_boundary
Content-Type: text/plain; charset="US-ASCII"
Content-Transfer-Encoding: 7bit
Greets!
Hooray for sound!
Happy Ears!
Al
- --part1_14b.25b220a.28f749fd_boundary
Content-Type: text/html; charset="US-ASCII"
Content-Transfer-Encoding: 7bit
<HTML><FONT FACE=arial,helvetica><BODY BGCOLOR="#ffffff"><FONT SIZE=2>Greets!
<BR>
<BR>Hooray for sound!
<BR>
<BR>Happy Ears!
<BR>Al
<BR>
<BR></FONT></HTML>
- --part1_14b.25b220a.28f749fd_boundary--
=========================================================================
From: ToobWiz@aol.com
Subject: Re: [JN] Fake Terror -- Let's not give Bill the "auto da fe"
Date: Thu, 11 Oct 2001 12:52:09 EDT
Source: Sound Digest Archive v02.n992
Please,
let's not start another "yes you did... I did not" thread. Most who will
object to this will object on the Subject of the posting alone. Use the
delete key if you don't like to read this sort of thing.
It probably isn't useful to the topic of audio to carry on, though if one
wants to stop all discourse with which he disagrees, then by all means, do
so. :-)
Cheers/Carron
=========================================================================
From: "PEARL Cust. Service" <custserv@pearl-hifi.com>
Subject: [JN] Fake Terror -- The Road to Dictatorship
Date: Thu, 11 Oct 2001 09:09:11 +0000
Source: Sound Digest Archive v02.n992
Hi All:
While this link might seem "off-topic" it is just about a relevant a thing
as I have come across in a long,long time.
http://www.whatreallyhappened.com/ARTICLE5/index
Also, I've lately sent three mails to the list that had attachments . .
none of which was posted.
I send these things for one reason and one reason only: to inform.
Bill Perkins - PEARL, Calgary, Canada.
=========================================================================
From: Norm Luttbeg <nluttbeg@politics.tamu.edu>
Subject: Re: [JN] Fake Terror -- The Road to Dictatorship
Date: Thu, 11 Oct 2001 11:37:16 -0500
Source: Sound Digest Archive v02.n992
I would question whether the purpose of this post is to "inform." Certainly
it is the oldest trick in the book for leaders to inspire loyalty because of
a external enemy, but unless Bill is suggesting that the CIA ran into the
WTB, what is he saying in this post?
on 10/11/01 4:09 AM, PEARL Cust. Service at custserv@pearl-hifi.com wrote:
> Hi All:
> While this link might seem "off-topic" it is just about a relevant a thing
> as I have come across in a long,long time.
>
> http://www.whatreallyhappened.com/ARTICLE5/index
>
> Also, I've lately sent three mails to the list that had attachments . .
> none of which was posted.
> I send these things for one reason and one reason only: to inform.
>
>
> Bill Perkins - PEARL, Calgary, Canada.
>
>
>
>
=========================================================================
From: "John Levreault" <jlevro@mediaone.net>
Subject: Re: [JN] Fake Terror -- The Road to Dictatorship
Date: Thu, 11 Oct 2001 14:14:48 -0400
Source: Sound Digest Archive v02.n992
If you like that, you'll especially like:
http://davidicke.www.50megs.com/icke/magazine/vol5/bush/bushb.htm and
http://www.skolnicksreport.com/
JL
- ----- Original Message -----
From: "PEARL Cust. Service" <custserv@pearl-hifi.com>
To: <Sound@lists.io.com>
Sent: Thursday, October 11, 2001 5:09 AM
Subject: [JN] Fake Terror -- The Road to Dictatorship
> Hi All:
> While this link might seem "off-topic" it is just about a relevant a
thing
> as I have come across in a long,long time.
>
> http://www.whatreallyhappened.com/ARTICLE5/index
>
> Also, I've lately sent three mails to the list that had attachments .
.
> none of which was posted.
> I send these things for one reason and one reason only: to inform.
>
>
> Bill Perkins - PEARL, Calgary, Canada.
>
>
>
>
=========================================================================
From: "Jay B. Haider" <einberliner@hotmail.com>
Subject: Re: [JN] Fake Terror -- The Road to Dictatorship (OT)
Date: Thu, 11 Oct 2001 16:41:50 -0400
Source: Sound Digest Archive v02.n992
On the theory that a lie repeated often enough and unchallenged becomes the
truth, I reply. My apologies to uninterested readers for this OT post.
There's some interesting (if common knowledge) stuff in there, but when the
author(s) enter the post-Cold War world, they lose it. In particular, they
display a complete and utter lack of knowledge about the situation in the
former Yugoslavia. They correctly say that there were no concentration camps
run by Bosnians in its common usage as a shorthand for the Muslim population
of Bosnia. (As opposed to the ethnic Serbs and Croats who also live in
Bosnia-Herzegovina.) They had neither the land or the resources in order to
do so. However, there were such camps run by one of their occupiers, the
Serbs. That is, when they did not simply decide to exterminate the Bosnian
population, as they did when they overran the so-called UN Safe Haven of
Sebrenica. (The war on Bosnia began essentially as the result of a
Hitler-Stalin style pact by Serbia's Milosevic and Croatia's Tudjman, who,
while still at war with each-other, decided to partition Bosnia between
them.)
Just as importantly, AMERICA DID ABSOLUTELY NOTHING ABOUT THE ATROCITIES
COMMITTED IN BOSNIA UNTIL MUCH AFTER 1992! The article seems to imply
otherwise. Bush pere just didn't care about the area, and Clinton didn't
either. Indeed, America did nothing, just as we abdicated our duties to the
world as leaders of the only remaining superpower in Rwanda. Well, that's
not quite true: they ramrodded an arms embargo on all combatants in the
former Yugoslavia through the UN, thereby denying the Bosnian Muslims the
chance to defend themselves. (The Bosnians, unlike the Serbs and even to a
lesser extent the Croats, had basically no AK-47s let alone tanks or
artillery l at the start of the conflict) The embargo wasn't particularly
effective, though. The Orthodox Serbs continued to be supplied by Russia,
the Catholic Croatians by Eastern Europe, and the Muslim Bosnians mostly by
Turkey, with some arms coming in from the Gulf States, Iran, and Pakistan.
By Kosovo, it became apparent to some of the smarter foreign policy thinkers
in the West, people such as Joshka Fischer (leader of the German
Green/Budnis 90 Party and since mid-1998 German Foreign Minister)and Strobe
Talbott (at the time Deputy US Secretary of State) that to not stop the
Serbian reign of terror in the Balkans could ultimately destablise Europe,
so they acted. Unfortunately, the way they did so, with airstrikes from high
above and great fear of using materiel that could more accurately stop the
Serbian war machine -- such as the Apache helicopters that stayed grounded
in Albania -- allowed the Serbs to largely finish the job.
If the authors of this webpage wanted real examples of government/opposition
conspiracies to grab and hold power from the last several years, they should
have tried these two:
1) In order to assert the domanance of Israel's Lebenraumpolitik over the
rights of the Palestinian people, Gen. Ariel Sharon (a member of the
Knesset, Israel's parliament, who was called a war criminal by that very
body for his 'indirect responsibility' for the massacres at the Sabra and
Shattila refugee camps during the 1982 Israeli invasion of Lebanon) marched
on the Dome of the Rock, the third holiest site in Islam, inside a phalanx
of Israeli stormtroopers and policemen. This action set off the second phase
of the Palestinian independence struggle, and the ensuing violence
catapulted Gen. Sharon into the office of Prime Minister.
2) The Russian's current war in Chechnya began following a terrorist attack
on two apartment buildings in the waning days of Boris Yeltsen's Presidency.
(The current Russian Federation President, Vladimir Putin, was Prime
Minister at the time, following stints in the FSB -- the sucessor to the KGB
- -- and the municipal government of St. Petersburg) The Russian government
immediately blamed the attack on "Chechen Bandits" and redoubled war efforts
in Chechnya. I don't have the report in front of me, but one of the big two
human rights NGOs (Amnesty Int'l or Human Rights Watch) had quite a
different opinion. The evidence, they said, pointed to the FSB!
The implication of your post seems to be suspecion that perhaps the people
who stand to gain the most from public reaction against the attacks (Defense
Secretary Donald Rumsfeld, de facto President Dick Cheney, Attorney General
and wannabe crusader who couldn't even beat a dead man to hold on to his
Senate seat John Ashcroft) were behind it. That seems quite far-fetched. Not
even Rummy and Cheney are THAT evil, I don't think. (I hope.) The attack was
carried out by a minimum of 20 or so people, possibly with the support of a
larger organisation. (As no evidence has actually been presented of the
involvement of bin Laden or anyone else, reasonable people will hold their
judgement.)
I quite agree with the basic idea you're attempting to convey, that America
has no business trying to overthrow the government of Afghanistan, let alone
reinstate the warlords of the Northern Alliance, whose rule made the
Taleban's success seem like a blessing.
Do I like the Taleban government? No, I don't. In a lot of ways, their
stupidity and ignorance of Islam makes their name -- translated as
"Students" -- laughable. But on balance their human rights record isn't
appreciably different from those of the governments of Israel, Saudi Arabia,
Algeria, Zimbabwe, or Egypt. I don't see America bombing Tel Aviv in attempt
to remove Gen. Sharon, or Harare in order to unseat Robert Mugabe, so why
attack Afghanistan? For that matter, I don't see bombs flying on Washington
to unseat our own dubiously-elected government.
Furthermore, they are fundamentally wrong in taking a legal matter (the
murder of civilians by other civilians is by definition a crime, no matter
how horrendous the scale) and turning it into a military matter. With a
fundamentalist like Ashcroft in charge of Justice, who is to stick up for
rule of law in the US? (We are, I guess.)
However, the anti-war position is one entirely defensible with facts and
evidence. There's no need to spread half-truths in attempts to keep keep
Rummy and Cheney from augmenting their terrorist credentials in the
mountains and valleys of Afghanistan, when the truth will work just fine.
Peace,
J
NP: The Guess Who, "American Woman"
_________________________________________________________________
Get your FREE download of MSN Explorer at http://explorer.msn.com/intl.asp
=========================================================================
From: "Daniel J. Marshall" <danmarshall@worldnet.att.net>
Subject: [JN] FA: Linaeum 10 and Linaeum Extremes.
Date: Wed, 25 Aug 1999 18:34:26 -0700
Source: Sound Digest Archive v02.n263
Hi All,
I listed these on ebay, yeah, I know, its uncouth, but I didn't think
most of you would be interested as they are not suitable for low-power
SE amps. The Lineaum 10s are quite nice high-end speakers listing at
$3,000. I have them at an opening bid of $800 with no reserve, and, so
far, no bid. The auction ends tonight. They are very silky, smooth and
forgiving of harshness, which most folks like, but is not everyone's cup
of tea. Your lady would probably like them. If you like bombastic,
knock-your-socks off, rattle-your-teeth sound, these may be too tame for
you. If you like something that just plain sounds good on all source
material, you would like these. They are soo smooth that even when
cranked, are not annoying, or fatiguing. And they sound good with SS
amps, and have an amazing amount of extended bass for 8 inch speakers,
well down into the low thirties. They are in quite solidly built tower
enclosures. There is no sense of wanting more bass or a sub when
listening to them, even when running them flat. They seem to handle
quite a lot of power, so you can crank them. Upgrades are teak wood
exterior Kimber bi-wiring, Cardas binding posts and sand filled bases.
I am trying to get back to housing my entire system in the three piece
Mediterrranean style enclosures I built many years ago and these don't
fit into the scheme of things. They sit out from the wall and have the
speakers up at listening level so you can get them properly positioned
for good sound. The Radio Shack LX-8s are not even in the same league,
no comparison, the 10s will easily blow them away. Anyway, have a
look-see, if interested. I have almost talked myself into wanting to
keep them. I had someone over the other day and he just raved about
them.
http://cgi3.ebay.com/aw-cgi/eBayISAPI.dll?ViewListedItems&userid=danmarshall@worldnet.att.net
Dan Marshall
=========================================================================
From: Paul Joppa <pdjoppa@home.com>
Subject: [JN] Re: falling woofers ...
Date: Thu, 23 Mar 2000 23:05:01 -0800
Source: Sound Digest Archive v02.n493
John Niven said:
> ...what would be the best way to design a speaker that would
> deliberately deliver a natural response that would be decreasing at
> 6dB/octave from 50Hz upward, and be usable up to 500Hz?
A large horn (cutoff << 50Hz) driven by a woofer with fs/QT = 50Hz
should do the job, if you have a spare room or two to fit the horn
into... it has to be a straight horn, not folded, to maintain good
response above 500Hz of course.
:^) Paul Joppa
=========================================================================
From: John Niven <jn@cypress.com>
Subject: Re: [JN] Re: falling woofers ...
Date: Fri, 24 Mar 2000 13:06:32 -0800
Source: Sound Digest Archive v02.n495
Paul (and all with an adventurous mind),
Obviously, due to the lack of a response, my question did not inspire
the list :-)
Perhaps I can explain more. The root of my thoughts were grounded in the
RIAA equilisation response. The music recorded on a LP has a response
(amongst other things) that falls off at 6db/octave from 500hz. So if
you listened to an LP, from the PU, through an amplifier that had a flat
frequency response, the bass would not be there. This would normally be
bad. However, if you feed this signal into a horn with a 500Hz cutoff,
this would be good! You already have one half of a bi-amped system with
no crossover. Now the RIAA equilisation also creates a rising response
at 6db/octave from 2122Hz. So to compensate for this I would want my
mid-range/upper horn to have a response that falls off at 6db/octave
from 2122Hz. So I just need to use a driver (cheap?) that has a poor
high frequency response and that would take care of the mids and highs.
It also occurs to me that for the mid/high frequency you could use a
small cheepo driver on an circular open baffle with a radius of 1.125 ft
which would have a cutoff of 500Hz (half the wavelength). Such a driver
may actually benefit from having its treble boosted by 6dB/octave from
2KHz. It would certainly be easy to build!
So to recap, the mids/highs come directly from the PU through an
amplifier (valve?) with a flat response from 500Hz to 2KHz and then
tailored to meet the drivers response above that (maybe flat or maybe
rolling off at 6db/octave if driver is a good one.
Now for the bass we need to take the PU output and feed it into an
amplifier/driver/loading-method with lots of gain at 50Hz but that has a
6db/octave falling response from 50Hz to compensate for the RIAA curve.
After 500Hz its response could fall off even faster. This was the start
of my previous question. I was wondering about some kind of bandpass box
only tuned to 50Hz... Would that work to 500hz?
I think of this as a system designed to play LP's with the minimum of
electronics. It seems to me that we spend to much time making speakers
with a flat response, that work with an amplifier that has a flat
response, that work with a PU preamp that then has to have a very
non-linear response! Bi-amping and no crossovers for free!
And if you must use the same system with a CD player, why not add some
compensation that makes its output look like a PU? I get the impression
that CD's tend to be this lists second choice anyway.
Put me out of my misery...point out the fatal flaw. Please.
Cheers,
John
Paul Joppa wrote:
>
> John Niven said:
> > ...what would be the best way to design a speaker that would
> > deliberately deliver a natural response that would be decreasing at
> > 6dB/octave from 50Hz upward, and be usable up to 500Hz?
>
> A large horn (cutoff << 50Hz) driven by a woofer with fs/QT = 50Hz
> should do the job, if you have a spare room or two to fit the horn
> into... it has to be a straight horn, not folded, to maintain good
> response above 500Hz of course.
>
> :^) Paul Joppa
- --
_\|/
Q John Niven (jn@cypress.com)
/ \ Staff Product Engineer
/ o\ Cypress Semiconductor
( \/ 3901 North First Street
|\ San Jose,CA 95134
| \ Telephone 408-456-1868
L L
=========================================================================
From: John Niven <jn@cypress.com>
Subject: Re: [JN] Re: falling woofers ...
Date: Fri, 24 Mar 2000 14:31:08 -0800
Source: Sound Digest Archive v02.n495
Roscoe,
I think you picked this up wrongly. The recorded music on the LP has a
RISING FR from 2122Hz @ 6db/octave (=20db/decade). So you need LESS gain
in the amplifier/loudspeaker as the freq increases to get a flat
response.
Keep thinking!
John :-)
Roscoe Primrose wrote:
> Well, given a 6dB/octave drop from 2122Hz to 20kHz, it takes almost 100
> times as much amplifier power at 20kHz if you don't do the RIAA EQ
> before the amp...
- --
_\|/
Q John Niven (jn@cypress.com)
/ \ Staff Product Engineer
/ o\ Cypress Semiconductor
( \/ 3901 North First Street
|\ San Jose,CA 95134
| \ Telephone 408-456-1868
L L
=========================================================================
From: Roscoe Primrose <roscoe@aiko.com>
Subject: Re: [JN] Re: falling woofers ...
Date: Fri, 24 Mar 2000 16:38:08 -0500
Source: Sound Digest Archive v02.n495
John Niven wrote:
Snip
>
> I think of this as a system designed to play LP's with the minimum of
> electronics. It seems to me that we spend to much time making speakers
> with a flat response, that work with an amplifier that has a flat
> response, that work with a PU preamp that then has to have a very
> non-linear response! Bi-amping and no crossovers for free!
>
> And if you must use the same system with a CD player, why not add some
> compensation that makes its output look like a PU? I get the impression
> that CD's tend to be this lists second choice anyway.
>
> Put me out of my misery...point out the fatal flaw. Please.
Well, given a 6dB/octave drop from 2122Hz to 20kHz, it takes almost 100
times as much amplifier power at 20kHz if you don't do the RIAA EQ
before the amp...
Peace
- --
Roscoe Primrose -- mailto:roscoe@aiko.com --
http://www.aiko.com/roscoe
"Once in a while you get shown the light
In the strangest of places if you look at it right." Robert Hunter
"640K ought to be enough for anybody" , Bill Gates, 1981
=========================================================================
From: Kurt Steffensen <kurt-steffensen@teliamail.dk>
Subject: Re: [JN] Re: falling woofers ...
Date: Sat, 25 Mar 2000 01:09:03 +0300
Source: Sound Digest Archive v02.n495
:-)
Actually , none of you is all right....
They need the same power , and more or less gain , will depend upon which you
choose for reference.
With three to choose from , you are both right..:-)
- - And you are both wrong ;-)
I will second John , keep thinking ;-)
- - Kurt ( This was a good weekend of topic )
John Niven wrote:
> Roscoe,
>
> I think you picked this up wrongly. The recorded music on the LP has a
> RISING FR from 2122Hz @ 6db/octave (=20db/decade). So you need LESS gain
> in the amplifier/loudspeaker as the freq increases to get a flat
> response.
>
> Keep thinking!
> John :-)
>
> Roscoe Primrose wrote:
>
> > Well, given a 6dB/octave drop from 2122Hz to 20kHz, it takes almost 100
> > times as much amplifier power at 20kHz if you don't do the RIAA EQ
> > before the amp...
>
> --
> _\|/
> Q John Niven (jn@cypress.com)
> / \ Staff Product Engineer
> / o\ Cypress Semiconductor
> ( \/ 3901 North First Street
> |\ San Jose,CA 95134
> | \ Telephone 408-456-1868
> L L
=========================================================================
From: Ed Billeci <tube@teleport.com>
Subject: [JN] FA: Lowther Medallions on ebay
Date: Sun, 7 Jan 2001 12:13:49 -0800
Source: Sound Digest Archive v02.n777
Shameless plug.
http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=1206392139
Thanks for the bandwidth.
Ed
http://www.teleport.com/~tube
=========================================================================
From: Jonathan Morrison <ppdiva@rcn.com>
Subject: [JN] Fanatic? Who's a fanatic? (really really off topic)
Date: Tue, 06 Jul 1999 20:39:19 -0400
Source: Sound Digest Archive v02.n197
I don't know if there are any other home coffee roasters on this list, but
if there are, I can strongly recommend the Hearthware roaster. I got one
about 2 weeks ago to replace an old Sirroco, and have been very pleased
with its results. I'm still experimenting with roasting times, but overall
it roasts much slower than the Sirroco, with a corresponding increase in
flavor depth. The Ethiopian harrar that I am using comes out very citrusy
with very high toned acidity and a little of the usual Harrar chocolate,
and the Timor decaf has a very sweet background. I am particularly
impressed by the fast bass of the Harrar.
The unit is too noisy, but that is my only complaint, and when I get the
settings right for the different roasts, with its good cooling cycle I can
just set the timer and leave the room. For $120 from www.sweetmarias.com
it's a good deal, and Tom at Sweetmarias has excellent prices on green
coffee. I figure that it will pay for itself in several months with the
savings over comparable quality coffees from $tarbucks or similar. JDM
P.S. The roasting chamber is a round glass thing, so maybe this isn't all
that far off topic...
=========================================================================
From: Dan Marshall <mdaniel7@uswest.net>
Subject: [JN] FA: Norelco FR Speakers
Date: Wed, 19 Jul 2000 06:38:22 -0700
Source: Sound Digest Archive v02.n607
Hi All,
Well, I decided to bail on the 12" Norelcos. They seem to be a hot item
on eBay nowdays. A pair of the next lower model (AD-5200Ms) just sold
there for $406, which I found delightfully surprising. Anyway, I want
to retain my current enclosures and they position full-range speakers
way too close to the floor for good stereo reproduction and they are of
such a style that they are not conducive to being raised to ear-level
height without becoming an eyesore, so, rather than use the Norelcos as
woofers I thought I might as well cash in on the FR craze and put some
true woofers I have to good use and use smaller satellite speakers for
the mid/top end. If interested, here is the eBay address:
http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=386135617
Dan Marshall
=========================================================================
From: russ arbuthnot <russ3@southern.com>
Subject: [JN] Fans
Date: Thu, 22 Feb 2001 12:37:20 -0600
Source: Sound Digest Archive v02.n815
Joe-kers,
My roommate has a pair of McIntosh 35 monoblocks (i don't know the exact
models, i'm a SE guy) with a big (6"sq.) fan blowing on each one. The fans
plug right into the monoblocks and start when you turn on the preamp. My
complaint is that they make quite a bit of noise which gets in the way of
listening. I realize that these fans might have been needed when the
system was initially installed as part of his grandmother's wall stereo or
whatever, but are they really needed now that they are upon an open
salamander style equipment rack?
This wouldn't be a problem if I could finish/finance a preamp for my
6SN7/300B amp. But until I do, his system gets a little more use because
of ease of use.
What do you guys think?
Thanks,
russ
=========================================================================
From: David Home <David_Home@creoscitex.com>
Subject: [JN] Fans of BG Type 'N' ?
Date: Tue, 6 Feb 2001 14:13:34 +0100
Source: Sound Digest Archive v02.n800
Hello all.
Recapping the crossovers in my Tannoy Monitor Golds. There are three in the
tweeter circuit, a 6.8uF, then a 1.5uF and then a 3.3uF shunting the
tweeter.
The bass driver has a single 16uF. Previous owner replaced all caps with
Solen, which I find too edgy for my tastes.
I replaced all with oilers and sound got much rounder and smoother, but also
slow and thick.
I was wondering if the BG type "N AC' would be worth the financial
investment. They have a 6.8uF and 15uF in the AC range. The others could be
built from the N range.
I was hoping someone would comment on the sound of these caps.
Also if the 'N' and 'NX' can take the currents of a tweeter circuit.
Regards, David
=========================================================================
From: Christian Rintelen <christian@rintelen.ch>
Subject: Re: [JN] Fans of BG Type 'N' ?
Date: Tue, 06 Feb 2001 14:58:29 +0100
Source: Sound Digest Archive v02.n800
David,
I have no experience with Black Gate caps in passive crossovers. However, I do
like the Mundorf tinfoil caps
<http://www.mundorf.com/english/bauteile/kondensatoren/mcap-znrechts.htm> and
I've also had good results with Hovland caps.
Christian
=========================================================================
From: Allen Wright <AllenVSE@compuserve.com>
Subject: [JN] Fans of BG Type 'N' ?
Date: Wed, 7 Feb 2001 05:13:44 -0500
Source: Sound Digest Archive v02.n800
david wrote:
>>> Previous owner replaced all caps with
Solen, which I find too edgy for my tastes<<<
Which Solens? They have some great caps and some sonic junk - IME.
I'm currently using their (actually the parent company - SCR) solid
tinfoil/polyprop caps in my speaker and electronics with great results. But
some of their other offerings don't sing for me.
Allen (VSE)
Then Christian has written:
>>>However, I do
like the Mundorf tinfoil caps<<<
Same thing - they are made in France by SCR and marketed under various
names around the world: Solen, Mundorf, Audyn etc. Often with the logo in
GOLD ink...
=========================================================================
From: "Jon Lane" <jhlane@reflexnet.net>
Subject: RE: [JN] Fans of BG Type 'N' ?
Date: Wed, 7 Feb 2001 07:37:54 -0700
Source: Sound Digest Archive v02.n800
> >>> Previous owner replaced all caps with
> Solen, which I find too edgy for my tastes<<<
>
> Which Solens? They have some great caps and some
> sonic junk - IME.
>
> I'm currently using their (actually the parent
> company - SCR) solid
> tinfoil/polyprop caps in my speaker and
> electronics with great results. But
> some of their other offerings don't sing for me.
>
> Allen (VSE)
>
> Then Christian has written:
>
> >>>However, I do
> like the Mundorf tinfoil caps<<<
>
> Same thing - they are made in France by SCR and
> marketed under various
> names around the world: Solen, Mundorf, Audyn
> etc. Often with the logo in
> GOLD ink...
The Axon tinfoils are quite good too. Probably a near twin
to the Solen/SCR. Distributed by Kimon Belles of ORCA
Design.
Jon Lane
=========================================================================
From: TubeGarden@aol.com
Subject: Re: [JN] Fans of BG Type 'N' ?
Date: Wed, 7 Feb 2001 12:45:22 EST
Source: Sound Digest Archive v02.n800
- --part1_44.b286c5b.27b2e3b2_boundary
Content-Type: text/plain; charset="US-ASCII"
Content-Transfer-Encoding: 7bit
In a message dated 2/7/01 3:21:53 AM US Mountain Standard Time,
AllenVSE@compuserve.com writes:
> Often with the logo in
> GOLD ink...
>
not Tin?
Happy Ears!
Al B^}
- --part1_44.b286c5b.27b2e3b2_boundary
Content-Type: text/html; charset="US-ASCII"
Content-Transfer-Encoding: 7bit
<HTML><FONT FACE=arial,helvetica><BODY BGCOLOR="#ffffff"><FONT SIZE=2>In a message dated 2/7/01 3:2
1:53 AM US Mountain Standard Time,
<BR>AllenVSE@compuserve.com writes:
<BR>
<BR>
<BR><BLOCKQUOTE TYPE=CITE style="BORDER-LEFT: #0000ff 2px solid; MARGIN-LEFT: 5px; MARGIN-RIGHT: 0px
; PADDING-LEFT: 5px">Often with the logo in
<BR>GOLD ink...
<BR></BLOCKQUOTE>
<BR>
<BR>not Tin?
<BR>
<BR>Happy Ears!
<BR>Al B^}
<BR>
<BR></FONT></HTML>
- --part1_44.b286c5b.27b2e3b2_boundary--
=========================================================================
From: "Bart Shepherd \(Home\)" <bart.s@bigpond.net.au>
Subject: RE: [JN] Fans of BG Type 'N' ?
Date: Wed, 7 Feb 2001 23:42:45 +1100
Source: Sound Digest Archive v02.n800
Hello David,
I have been thinking about this issue and would like to suggest a different
way of looking at it.
Many people think they can improve equipment by replacing components with
"better" ones or even "the best" ones.
Designers and manufacturers actually make many decisions in product design
and contrary to some opinions, not all of them based on cost.
This loudspeaker actually has a natural roll-off with frequency in the HF
horn. The "cross-over" is more than a cross-over and is actually also an HF
boost filter. This may have been tuned by ear by the designers who have had
many years of vast exerience with this very issue. The components they used
may have been imperfect but actually achieved a balanced sound.
Before doing anything else it may be perhaps wise to attempt to restore it
to original condition by only replacing components where required and doing
the replacement with new components as close to the originals as possible. I
would suggest your measure all the components and only replace those now out
of tolerance - the original capacitors may be long gone but at least check
the resistor values.
It is possible that the modifications have inadvertently boosted the HF too
much. Also check no cap values have been changed!
It may be worhwhile to contact the manufacturers and ask their
recommendation of the best replacement brand and type.
Cheers,
Bart
- -----Original Message-----
From: owner-sound@lists.io.com [mailto:owner-sound@lists.io.com]On
Behalf Of David Home
Sent: Wednesday, 7 February 2001 12:14 AM
To: Sound (E-mail)
Subject: [JN] Fans of BG Type 'N' ?
Hello all.
Recapping the crossovers in my Tannoy Monitor Golds. There are three in the
tweeter circuit, a 6.8uF, then a 1.5uF and then a 3.3uF shunting the
tweeter.
The bass driver has a single 16uF. Previous owner replaced all caps with
Solen, which I find too edgy for my tastes.
I replaced all with oilers and sound got much rounder and smoother, but also
slow and thick.
I was wondering if the BG type "N AC' would be worth the financial
investment. They have a 6.8uF and 15uF in the AC range. The others could be
built from the N range.
I was hoping someone would comment on the sound of these caps.
Also if the 'N' and 'NX' can take the currents of a tweeter circuit.
Regards, David
=========================================================================
From: Allen Wright <AllenVSE@compuserve.com>
Subject: RE: [JN] Fans of BG Type 'N' ?
Date: Thu, 8 Feb 2001 04:27:17 -0500
Source: Sound Digest Archive v02.n800
Jon wrote:
>>>The Axon tinfoils are quite good too. Probably a near twin
to the Solen/SCR. Distributed by Kimon Belles of ORCA
Design<<<
Yes - another re-lableing of the same SCR cap.
Allen (VSE)
=========================================================================
From: "Epstein, Jeremy" <JEpstein@ndbcap.com>
Subject: [JN] Fans of BG Type 'N' ?
Date: Thu, 8 Feb 2001 09:23:05 -0500
Source: Sound Digest Archive v02.n801
Note that another Solen relabel is available fairly cheaply from Angela
Instruments, www.angela.com
- -j
=========================================
Jeremy Epstein........jepstein@ndbcap.com
=========================================
=========================================================================
From: "Fred Volz" <fcv@emotiveaudio.com>
Subject: Re: [JN] Fans of BG Type 'N' ?
Date: Thu, 8 Feb 2001 09:25:57 -0500
Source: Sound Digest Archive v02.n801
Hovland MusiCaps are polypropylene and aluminum foil. Solens and SCR and
Axon caps may all roll out of the same plant, but they do not all sound the
same. By comparison, the Axon tin foil caps (are there SCR versions of these
as well?) are much nicer than the standard Axon and Solen metalized parts.
But, the Hovlands are in another class entirely from any of the
aforementioned caps. They sound MUCH better and are very well made. This is
why they are more expensive than the other caps (quality=cash).
If the proposed use for the caps in question is in a speaker crossover (and
if cost is an issue), why not try the ASC motor start caps. These are
metalized polypropylene in vegetable oil (aluminum can type). I've not used
them in a crossover yet, but have been told they sound extremely good. In
power supplies, they sound better then any other cap I've tried yet. And,
they are VERY cheap. I'm almost embarrassed to admit it, but they sound way
TOO good in coupling applications, as well.
Fred Volz
fcv@emotiveaudio.com
- ----- Original Message -----
From: "John Hancock" <John_Hancock@swissre.com>
To: <sound@lists.io.com>
Sent: Thursday, February 08, 2001 5:42 AM
Subject: RE: [JN] Fans of BG Type 'N' ?
>
>
>
> Just to be clear, I believe all of these caps are metallized
polypropylene.
> The Mundorfs that Christian is talking about are tinfoil and polypropylene
> (like the Hovlands), which have a lower electrostatic resistance. The
> Mundorfs are, by the way, quite a bit cheaper than the Hovlands, at least
> here in Europe.
>
> John
>
> Jon wrote:
> >>>The Axon tinfoils are quite good too. Probably a near twin
> to the Solen/SCR. Distributed by Kimon Belles of ORCA
> Design<<<
>
> Allen wrote:
> >Yes - another re-lableing of the same SCR cap.
>
>
=========================================================================
From: "John Hancock" <John_Hancock@swissre.com>
Subject: RE: [JN] Fans of BG Type 'N' ?
Date: Thu, 8 Feb 2001 11:42:12 +0100
Source: Sound Digest Archive v02.n801
Just to be clear, I believe all of these caps are metallized polypropylene.
The Mundorfs that Christian is talking about are tinfoil and polypropylene
(like the Hovlands), which have a lower electrostatic resistance. The
Mundorfs are, by the way, quite a bit cheaper than the Hovlands, at least
here in Europe.
John
Jon wrote:
>>>The Axon tinfoils are quite good too. Probably a near twin
to the Solen/SCR. Distributed by Kimon Belles of ORCA
Design<<<
Allen wrote:
>Yes - another re-lableing of the same SCR cap.
=========================================================================
From: "Mindaugas" <mk@is.lt>
Subject: Re: [JN] Fans of BG Type 'N' ?
Date: Thu, 8 Feb 2001 17:15:48 +0200
Source: Sound Digest Archive v02.n801
> If the proposed use for the caps in question is in a speaker crossover
(and
> if cost is an issue), why not try the ASC motor start caps. These are
> metalized polypropylene in vegetable oil (aluminum can type). I've not
used
> them in a crossover yet, but have been told they sound extremely good. In
> power supplies, they sound better then any other cap I've tried yet. And,
> they are VERY cheap. I'm almost embarrassed to admit it, but they sound
way
> TOO good in coupling applications, as well.
Any source for these?
Mindaugas
=========================================================================
From: "Jon Lane" <jhlane@reflexnet.net>
Subject: RE: [JN] Fans of BG Type 'N' ?
Date: Thu, 8 Feb 2001 17:51:29 -0700
Source: Sound Digest Archive v02.n801
> Just to be clear, I believe all of these caps are
> metallized polypropylene.
> The Mundorfs that Christian is talking about are
> tinfoil and polypropylene
> (like the Hovlands), which have a lower
> electrostatic resistance. The
> Mundorfs are, by the way, quite a bit cheaper
> than the Hovlands, at least
> here in Europe.
>
> John
>
> Jon wrote:
> >>>The Axon tinfoils are quite good too.
> Probably a near twin
> to the Solen/SCR. Distributed by Kimon Belles of ORCA
> Design<<<
>
> Allen wrote:
> >Yes - another re-lableing of the same SCR cap.
Actually, the Axon tinfoil *is* tinfoil - they're far
heavier than the standard black metalized caps. They are
white in color, have solid copper leads, and sound quite
relaxed and spacious. You may have to check with ORCA for
the details.
Jon Lane
=========================================================================
From: "Bart Shepherd \(Home\)" <bart.s@bigpond.net.au>
Subject: RE: [JN] Fans of BG Type 'N' ?
Date: Fri, 9 Feb 2001 17:44:12 +1100
Source: Sound Digest Archive v02.n801
I used to use these Axon tinfoils as couplers in my 211 amp. ( 6SN7 to 6SN7
(parallel, no smear ) cathode follower ).
Changed to Hovland which I much prefer ( Axom very clean and extended but
Hovland better, richer harmonic sructure somehow )
Both 0.2uf
YMMV
Cheers,
Bart
- -----Original Message-----
From: owner-sound@lists.io.com [mailto:owner-sound@lists.io.com]On
Behalf Of Jon Lane
Sent: Friday, 9 February 2001 11:51 AM
To: sound@lists.io.com
Subject: RE: [JN] Fans of BG Type 'N' ?
> Just to be clear, I believe all of these caps are
> metallized polypropylene.
> The Mundorfs that Christian is talking about are
> tinfoil and polypropylene
> (like the Hovlands), which have a lower
> electrostatic resistance. The
> Mundorfs are, by the way, quite a bit cheaper
> than the Hovlands, at least
> here in Europe.
>
> John
>
> Jon wrote:
> >>>The Axon tinfoils are quite good too.
> Probably a near twin
> to the Solen/SCR. Distributed by Kimon Belles of ORCA
> Design<<<
>
> Allen wrote:
> >Yes - another re-lableing of the same SCR cap.
Actually, the Axon tinfoil *is* tinfoil - they're far
heavier than the standard black metalized caps. They are
white in color, have solid copper leads, and sound quite
relaxed and spacious. You may have to check with ORCA for
the details.
Jon Lane
=========================================================================
From: David Home <David_Home@creoscitex.com>
Subject: RE: [JN] Fans of BG Type 'N' ?
Date: Fri, 9 Feb 2001 22:39:29 +0100
Source: Sound Digest Archive v02.n802
Hello Allen.
I have tried various types of aluminum foil types. SCR, Solen and Avon
branded.
I am glad to hear that you have had good results with the tinfoil types, I
was wondering how these sounded too.
I believe that the tinfoil SCR caps largest size is 1.5uF. My speakers need
a 1.5uF but also a 3.3uF and more difficultly a 6.8uF and a 16uF. So the BGs
look quite appealing in the larger sizes...
Regards, David
- -----Original Message-----
From: Allen Wright [mailto:AllenVSE@compuserve.com]
Sent: Wednesday, February 07, 2001 11:14 AM
To: AAJoeNet
Subject: [JN] Fans of BG Type 'N' ?
david wrote:
>>> Previous owner replaced all caps with
Solen, which I find too edgy for my tastes<<<
Which Solens? They have some great caps and some sonic junk - IME.
I'm currently using their (actually the parent company - SCR) solid
tinfoil/polyprop caps in my speaker and electronics with great results. But
some of their other offerings don't sing for me.
Allen (VSE)
Then Christian has written:
>>>However, I do
like the Mundorf tinfoil caps<<<
Same thing - they are made in France by SCR and marketed under various
names around the world: Solen, Mundorf, Audyn etc. Often with the logo in
GOLD ink...
=========================================================================
From: David Home <David_Home@creoscitex.com>
Subject: RE: [JN] Fans of BG Type 'N' ?
Date: Sun, 11 Feb 2001 21:04:11 +0100
Source: Sound Digest Archive v02.n803
Thanks for the thoughts Bart.
The previous owner replaced all the original caps with Solens, but I would
guess that the smaller caps were film and the larger sizes non polar
electrolytics. I Would not dream of changing values!
I understrand the functioning of this crossover and the wisdom of respecting
the original engineers choices.
Regards, David
- -----Original Message-----
From: Bart Shepherd (Home) [mailto:bart.s@bigpond.net.au]
Sent: Wednesday, February 07, 2001 1:43 PM
To: David Home; Sound (E-mail)
Subject: RE: [JN] Fans of BG Type 'N' ?
Hello David,
I have been thinking about this issue and would like to suggest a different
way of looking at it.
Many people think they can improve equipment by replacing components with
"better" ones or even "the best" ones.
Designers and manufacturers actually make many decisions in product design
and contrary to some opinions, not all of them based on cost.
This loudspeaker actually has a natural roll-off with frequency in the HF
horn. The "cross-over" is more than a cross-over and is actually also an HF
boost filter. This may have been tuned by ear by the designers who have had
many years of vast exerience with this very issue. The components they used
may have been imperfect but actually achieved a balanced sound.
Before doing anything else it may be perhaps wise to attempt to restore it
to original condition by only replacing components where required and doing
the replacement with new components as close to the originals as possible. I
would suggest your measure all the components and only replace those now out
of tolerance - the original capacitors may be long gone but at least check
the resistor values.
It is possible that the modifications have inadvertently boosted the HF too
much. Also check no cap values have been changed!
It may be worhwhile to contact the manufacturers and ask their
recommendation of the best replacement brand and type.
Cheers,
Bart
- -----Original Message-----
From: owner-sound@lists.io.com [mailto:owner-sound@lists.io.com]On
Behalf Of David Home
Sent: Wednesday, 7 February 2001 12:14 AM
To: Sound (E-mail)
Subject: [JN] Fans of BG Type 'N' ?
Hello all.
Recapping the crossovers in my Tannoy Monitor Golds. There are three in the
tweeter circuit, a 6.8uF, then a 1.5uF and then a 3.3uF shunting the
tweeter.
The bass driver has a single 16uF. Previous owner replaced all caps with
Solen, which I find too edgy for my tastes.
I replaced all with oilers and sound got much rounder and smoother, but also
slow and thick.
I was wondering if the BG type "N AC' would be worth the financial
investment. They have a 6.8uF and 15uF in the AC range. The others could be
built from the N range.
I was hoping someone would comment on the sound of these caps.
Also if the 'N' and 'NX' can take the currents of a tweeter circuit.
Regards, David
=========================================================================
From: longrie@mmace.nrl.navy.mil
Subject: [JN] Fantasia 2000
Date: Mon, 06 Mar 2000 10:43:14 +0000
Source: Sound Digest Archive v02.n475
>From: Kurt Steffensen <kurt-steffensen@teliamail.dk>:
>
>Steve Bench has sent me a CD soundtrack ( new ) , with Disney's "Fantasia
>2000".....( Thanks a lot , Steve :-)
>You can count on that I will play that for the guys..
>The recording is probably meant for cinema use , but it is really good , and
>it delivers some of the most impressing sub bass , I have ever heard....
>With my new amplifiers the whole house is literally shaking....!!
>
>A scaring experience....Ask my neighbours..........;-)
>
>I hope you all had a nice weekend.
>
>- - Five months to go :-)
>
>- - Kurt
Hi Kurt,
I concur with your comments on the Fantasia 2000 CD, and of course,
also with gratitude to Steve Bench. Most gracious and capable fellow.
Steve has also sent a copy of the Fantasia 2000 limited edition CD
here. Our little Washington tube society will hear some excerpts
from this CD in our March gathering.
I have listened to F 2000 on my modest hi fi system and the music
is surely astounding. Great dynamics and range. Have a house dog
who is usually hard to motivate. During one quiet passage there
came a tremendous bass drum thwack. Dog leaped up and ran out of
the room, looking back frightfully. That has never happened before,
and I tend to play things loud. Very startling even to one who knows
it is coming. There are also some very deep notes that my system
can only hint at. Am looking forward to hearing this through some fine
systems. Thanks again, Steve, we'll report in.
respectfully
gary
"If I have seen further than my peers,
it is because I have stood on their toes."
=========================================================================
From: "blackcat electronics" <blackcat.e@virgin.net>
Subject: [JN] FAO Ross Lahlum
Date: Thu, 24 Jun 1999 21:11:37 +0100
Source: Sound Digest Archive v02.n187
Sorry to everyone !
Ross,
Please get in touch...all my messages are being bounced.
Graham.
blackcat electronics
blackcat.e@virgin.net
01253 855294 UK
=========================================================================
From: "Daniel J. Marshall" <danmarshall@worldnet.att.net>
Subject: [JN] FA: Peerless PT, KT88, GZ34s, Radios, etc.
Date: Fri, 19 May 2000 13:48:08 -0700
Source: Sound Digest Archive v02.n552
Hi All,
Have a look, if interested in any of the above. Its all in nice cond.
http://cgi6.ebay.com/aw-cgi/eBayISAPI.dll?ViewListedItems&userid=danmarshall@worldnet.att.net
DM
=========================================================================
From: rfrancis@glasscity.net
Subject: [JN] FA: PP OPT, Tubes, Manuals, more
Date: Wed, 12 Apr 2000 19:31:35 -0700
Source: Sound Digest Archive v02.n518
I listed a bunch of stuff on ebay. So shoot me.
Or go take a look at:
http://cgi3.ebay.com/aw-cgi/eBayISAPI.dll?MfcISAPICommand=ViewListedItems&userid=tubino
There's a nice PP OPT that will go cheap, methinks. I plan to
put a lot more stuff up there -- but if you come to Toledo (it's
GOTTA be closer than Hoboken for SOMEONE!) I'll fix you up right
square. Anyone need a transformer with two 12vct windings, 2.5A
each?
Thanks for looking!
Rick
- -----
Sent using MailStart.com ( http://MailStart.Com/welcome.html )
The FREE way to access your mailbox via any web browser, anywhere!
=========================================================================
From: David Crittle <retrovox@bigpond.com>
Subject: [JN] FA: PP OPT, Tubes, Manuals, more
Date: Thu, 13 Apr 2000 13:33:01 +1000
Source: Sound Digest Archive v02.n518
>From: rfrancis@glasscity.net
>To: Sound@io.com
>I listed a bunch of stuff on ebay. So shoot me.
>
>Or go take a look at:
>http://cgi3.ebay.com/aw-cgi/eBayISAPI.dll?MfcISAPICommand=ViewListedItems&useri
>d=tubino
Better make that two bullets. Hey Joe......wygwtgiyh
http://cgi6.ebay.com/aw-cgi/eBayISAPI.dll?ViewListedItems&userid=retrovox
shows my current listing, may even contain some useful items! It's really
starting to pile up down here, I will never ever possibly use all the
components accumulated. I'm clearing a lot of excess tubes of all types
right now.
David Crittle
____________________________
Visit the Retrovox Where?house at
http://www.users.bigpond.com/retrovox
____________________________
Some pics at
http://albums.photopoint.com/j/AlbumList?u=149682
____________________________
If you never did, you should. These things are fun, and fun is good.
(Dr Seuess)
=========================================================================
From: pitoyo@avebe.com.sg
Subject: [JN] FA: PP OPT, Tubes, Manuals, more
Date: Fri, 14 Apr 2000 09:25:53 +0800
Source: Sound Digest Archive v02.n520
>From: rfrancis@glasscity.net
>To: Sound@io.com
>I listed a bunch of stuff on ebay. So shoot me.
>
>Or go take a look at:
>http://cgi3.ebay.com/aw-cgi/eBayISAPI.dll?MfcISAPICommand=ViewListedItems&useri
>d=tubino
Better make that two bullets. Hey Joe......wygwtgiyh
http://cgi6.ebay.com/aw-cgi/eBayISAPI.dll?ViewListedItems&userid=retrovox
shows my current listing, may even contain some useful items! It's really
starting to pile up down here, I will never ever possibly use all the
components accumulated. I'm clearing a lot of excess tubes of all types
right now.
David Crittle
____________________________
Visit the Retrovox Where?house at
http://www.users.bigpond.com/retrovox
____________________________
Some pics at
http://albums.photopoint.com/j/AlbumList?u=149682
____________________________
If you never did, you should. These things are fun, and fun is good.
(Dr Seuess)
=========================================================================
From: "Ed Coleman" <ecoleman@whidbey.net>
Subject: Re: [JN] FA: PP OPT, Tubes, Manuals, more and more!
Date: Wed, 12 Apr 2000 21:06:29 -0700
Source: Sound Digest Archive v02.n518
Hey Joes,where ya going with that Gattling gun ? (shoot me too!)
I have stuff on ebay too.
7591 vacuum tube
>http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=302248726
Dynaco tube tuner FM-3
http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=303926655
thanks Ed
- -----Original Message-----
From: David Crittle <retrovox@bigpond.com>
To: sound@lists.io.com <sound@lists.io.com>
Date: Wednesday, April 12, 2000 8:32 PM
Subject: [JN] FA: PP OPT, Tubes, Manuals, more
>>From: rfrancis@glasscity.net
>>To: Sound@io.com
>>I listed a bunch of stuff on ebay. So shoot me.
>>
>>Or go take a look at:
>>http://cgi3.ebay.com/aw-cgi/eBayISAPI.dll?MfcISAPICommand=ViewListedItems&
useri
>>d=tubino
>
>
>Better make that two bullets. Hey Joe......wygwtgiyh
>
>http://cgi6.ebay.com/aw-cgi/eBayISAPI.dll?ViewListedItems&userid=retrovox
>
>shows my current listing, may even contain some useful items! It's really
>starting to pile up down here, I will never ever possibly use all the
>components accumulated. I'm clearing a lot of excess tubes of all types
>right now.
>
>David Crittle
>____________________________
>Visit the Retrovox Where?house at
>http://www.users.bigpond.com/retrovox
>____________________________
>Some pics at
>http://albums.photopoint.com/j/AlbumList?u=149682
>____________________________
>If you never did, you should. These things are fun, and fun is good.
>(Dr Seuess)
>
>
=========================================================================
From: Jeff Mai <j.mai.lists@home.com>
Subject: [JN] FA - RCA MI-9449 15 inch woofer - Alnico
Date: Mon, 19 Mar 2001 07:28:06 -0700
Source: Sound Digest Archive v02.n837
Thought some of you might be interested in this woofer I'm auctioning:
http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=1221955949
As of this email, the bid is at $27 which is very cheap! Less than
two days are left on the auction.
Thanks for the BW.
Jeff
=========================================================================
From: "Aaron Bohnen" <bohnen@unixg.ubc.ca>
Subject: [JN] FA: regulated high voltage supplies on Ebay...
Date: Sat, 4 Dec 1999 16:08:45 -0800
Source: Sound Digest Archive v02.n354
Hi everyone,
I'm really concentrating on lightening my audio-related equipment load
before the spectre of having to move in June.
I've put a couple of high voltage supplies up on Ebay:
One is a Kefco 0-500 VDC @ 150 mA also has 6.3 VAC heater supply:
http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=213978226
The second one is a Lambda #71 0-500 VDC @ 200 mA, 0-200 VDC bias, 6.3
VAC @ 10 A heaters. Both are adjustable, regulated, etc.:
http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=213989101
Thanks!
Aaron
___________________________________________________________
Aaron Bohnen email: bohnen@unixg.ubc.ca
- -Ph.D. Student, Civil Engineering Department, U.B.C.
- -website: http://www.civil.ubc.ca/home/bohnen
=========================================================================
From: "PEARL Cust Serv" <custserv@pearl-hifi.com>
Subject: [JN] FAR off topic - was: Worlds Cheapest OPT
Date: Mon, 05 Jun 2000 17:42:54 -0600
Source: Sound Digest Archive v02.n566
TubeGarden Commented
> robert.m.danielak@lmco.com writes:
>
>> term "trannie".
>>>> could be transformer or transmission....
>>> or transistor...
> . . . or a former guy who had a "lopitoffofme."
> Happy Ears!
> Al B^}
Fyi, they don't "lopitoff", they turn it outside in.
Bill - PEARL, Inc.
=========================================================================
From: "PEARL Cust Serv" <custserv@pearl-hifi.com>
Subject: Re: [JN] FAR off topic - was: Worlds Cheapest OPT
Date: Mon, 05 Jun 2000 20:49:55 -0600
Source: Sound Digest Archive v02.n567
Happy ears wrote:
>
> OK, but first they take the insides out - ouch!
>
> Happy Ears and other parts!
Now *that's* funny . . . lol
> Al B^}
BP
=========================================================================
From: TubeGarden@aol.com
Subject: Re: [JN] FAR off topic - was: Worlds Cheapest OPT
Date: Mon, 5 Jun 2000 22:06:36 EDT
Source: Sound Digest Archive v02.n567
In a message dated 6/5/00 4:45:30 PM US Mountain Standard Time,
custserv@pearl-hifi.com writes:
> they turn it outside in.
OK, but first they take the insides out - ouch!
Happy Ears and other parts!
Al B^}
=========================================================================
From: William Hunt <wjhunt@ccnet.com>
Subject: [JN] fast bass?
Date: Mon, 01 Feb 1999 23:35:23 -0800
Source: Sound Digest Archive v02.n021
A comment on the subject of fast bass.
I have 3 way speakers with an active crossover ahead of the power amps.
The bass to mid crossover is about 325 Hz with a 24 dB / octive slope.
The crossover has on/off switches for each driver - very useful for
verifying that everything is hooked up as it should be. Several times I
have turned off the mid and high frequency drivers and just listened to
the bass drivers. The result is always a bit shocking - quite muddy,
indistinct sound with no transients. Even bass sounds like drums and
double bass strings sound muddy and hard to identify. Boy, that is slow
bass. Of course, the bass sounds quite good when all drivers are
playing.
This isn't a profound experiment but it does illustrate a basic idea:
an high frequency transients are being routed to the mid and high
frequency drivers.
As a description of a physical effect, fast bass sounds like a
contradiction. The phrase can't mean what the words suggest so it means
something else. But it is really just poetry rather than a description
of reality.
Bill Hunt
=========================================================================
From: Mattijs de Vries <mdevries@avvt.com>
Subject: Re: [JN] fast bass?
Date: Tue, 02 Feb 1999 10:17:53 -0100
Source: Sound Digest Archive v02.n021
Hello Bill (and others),
>I have 3 way speakers with an active crossover ahead of the power amps.
>The bass to mid crossover is about 325 Hz with a 24 dB / octive slope.
I think your problem lies here already. Active crossovers also have a
transient response. If not proper designed they can work very good and give
lineair frequency response, but they can have very bad transients. I
experimented a lot with my active two way system, with the bass (JBL 2226
frontloaded with a horn and backloaded with bassreflex) cut off at 150 Hz.
I tried many different filter approaches, 4th order, 3rd order, both Bessel
and Butterworth settings. The fourth order I never could get to work, third
order only one way. I came out with a cascade of three first order filters
which works very well. My bass is very fast, even without the top
frquencies. Big japanese drums really sound like membranes and the bass has
punch (you can feel it) even at very low sound levels.
Of course this also needs good cables (van den Hul Revelation) and a good
poweramplifier (Modified Aaron 3) to control it. Also the bass cabinet has
to be proper designed, this also can make a very big differenece... If you
have bass reflex, sometime s damping the pipes very lightly will make an
improvement. If that is the case, you know someone has flunked again and
designed a bass cabinet at Butterworth quality... Very nice for midisets,
but for high end audio really no good, unfortunately it is done very often
(when do they learn...)...
>This isn't a profound experiment but it does illustrate a basic idea:
>an high frequency transients are being routed to the mid and high
>frequency drivers.
Of course they are, the sound is not only the basic frequency. The sound is
made by the basic frequency with a spectrum of higher harmonics. What else
would make the difference between a violine and a voice doing the same
tone. You cannot see the basic frqeuncy seperate from the rest. It is thus
the case of getting the whole spectrum fast, at the same time and with good
quality at your listening place. If everything is right, you're there.
Being pushed in the couch by a very tight and fast bass playing is a great
experience!
Have fun,
_______
| _____ | MachMat, Mattijs de Vries
/ | | \ Top-Fi audio equipment, Tube sales
| | ||| | | Distributor AVVT Benelux
| | ||| | | ------------------------------------------------
| | ||| | | E-mail : MdeVries@AVVT.COM (Private)
| | ||| | | MachMat@AVVT.COM (Business)
| |_____| | URL : HTTP://WWW.AVVT.COM/machmat/
\ ||| / Adress : Campuslaan 41-214, 7522 NG, Enschede
|/_|_\| Country : The Netherlands, Europe
| | Phone : 0031-53-4895091, Fax : 0031-53-4357234
|_____| ------------------------------------------------
|| || Designing is the art of making compromises.
=========================================================================
From: "Ian McPhail" <i.mcphail@rmit.EDU.AU>
Subject: [JN] re: fast bass
Date: Thu, 17 Feb 2000 11:10:43 +1000
Source: Sound Digest Archive v02.n450
For the last few Australian Rules Football Grand Finals, an F18
comes in low over Melbourne then stands on its tail over the arena
and proceeds to disappear vertically, very quickly and very loudly.
I live several miles from the event, the bass even from here is
awesome, unfortunately going supersonic over the city is not
allowed.
regards Ian
Ian McPhail i.mcphail@rmit.edu.au
RMIT Chem and Met Eng Dept 110
GPO Box 2476V
Melbourne 3001
Australia
tel +61 3 9925 2408
tel +61 3 9925 3326
fax +61 3 9925 3746
=========================================================================
From: TubeGarden@aol.com
Subject: Re: [JN] re: fast bass
Date: Thu, 17 Feb 2000 10:02:22 EST
Source: Sound Digest Archive v02.n451
GJN!
My latest
AXIS: BOLD AS LOVE
Feng Shui speaker array has the tweeters firing East/West, The double back to
back series mids firing Up/Down (omni!) and the woofers firing North/South.
I have made it to Seggun Bass!
Scoring Position!
Happy Ears!
Al B^}
=========================================================================
From: "Jon Lane" <jhlane@email.msn.com>
Subject: RE: [JN] re: fast bass
Date: Mon, 21 Feb 2000 20:33:01 -0700
Source: Sound Digest Archive v02.n458
> GJN!
LOL!
Jon
=========================================================================
From: Martin Seddon <mseddon@iinet.net.au>
Subject: [JN] fast motorbikes and chasing girls
Date: Tue, 30 Nov 1999 19:33:35 +0000
Source: Sound Digest Archive v02.n348
Joes,
Here I am, hotel room in Melbourne, plugged into joenet, learning the arcane
secrets of the twilight zone - and listening on a Toshiba laptop.
Now anyone who's got a Toshiba knows it's the most excruciating audio device
ever invented, after tinnitus. But Putamayo's Cuba is playing and I'm
snapping fingers - rythmm, pace - yeah! Which just goes to show.
Just to colour in some of the characters (and sounds) around, I was kindly
invited by one Hugh Dean to visit last Sunday. An affable fellow and true
gentleman, as you would guess, living in unhurried audio harmony, with
friends and family drifting in and out.
So thus the Glass Harmony, a remarkable 2 stage 6SL7 input/mosfet output
machine. 'Joe buys a Krell'. No, I've never heard a Krell, it's just how I
imagine that kind of authority. It boogies - so this is fast bass, I
grinned. And sweet too.
Well I hope Hugh sticks a boiler plate on the front and sells them for 20
grand a-piece. Not as much fun as fast motorbikes and chasing girls, says
Hugh, but quite acceptable, at our age.
Yes, indeed. Thanks, Hugh.
Martin
=========================================================================
From: TubeGarden@aol.com
Subject: Re: [JN] fast motorbikes and chasing girls
Date: Tue, 30 Nov 1999 07:15:19 EST
Source: Sound Digest Archive v02.n349
In a message dated 11/30/99 4:44:25 AM US Mountain Standard Time,
mseddon@iinet.net.au writes:
> Not as much fun as fast motorbikes and chasing girls, says
> Hugh, but quite acceptable, at our age.
Greets Jeets Neets,
I still have my brand new, then, 1969 BSA 750cc Rocket 3.
And I chased her 'til she caught me :)
These are some of the dreams the music floats me thru...
Happy Ears!
Al B^}
=========================================================================
From: "PEARL Cust Serv" <custserv@pearl-hifi.com>
Subject: Re: [JN] fast motorbikes and chasing girls
Date: Tue, 30 Nov 1999 09:25:15 -0700
Source: Sound Digest Archive v02.n349
> Greets Jeets Neets,
>
> I still have my brand new, then, 1969 BSA 750cc Rocket 3.
HEY ! ! ! I had one of those too . . . . with the "Buck Rogers"
mufflers, what a sound ! ! !
God, I was all of 19 and short of dual quad hemis it was the fastest
thing on the road to 115mph.
What I bike and how I **wish** I still had mine . . . No brakes though,
and that CLUTCH, my left hand looked liked a transplant from Godzilla
> And I chased her 'til she caught me :)
>
> These are some of the dreams the music floats me thru...
>
> Happy Ears!
> Al B^}
Bill - PEARL, Inc.
=========================================================================
From: Scott Walters <sfwalters@worldnet.att.net>
Subject: Re: [JN] fast motorbikes and chasing girls
Date: Tue, 30 Nov 1999 20:34:28 -0500
Source: Sound Digest Archive v02.n349
Mine was a 65 Triumph 650 Trophy, and in the same stable an 87 Harley
FLST-C; Blue and Creme S&S Super Andrews cam And Paughco Fishtails.
The Trumpet had grit, The hog had command authority, She had red hair
and was shopping for a convent...
> > And I chased her 'til she caught me :)
> >
Scott
=========================================================================
From: Tim_Bailey@medibank.com.au
Subject: Re: [JN] fast motorbikes and chasing girls
Date: Wed, 1 Dec 1999 16:21:12 +1100
Source: Sound Digest Archive v02.n349
****************************************************************
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received this message in error please notify Medibank
Private Ltd immediately. Any views expressed in this
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****************************************************************
, sfwalters@worldnet.att.net re 'bikes;
mine were:
A Bultaco 250 single (2stroke) sports racer and,
one of those murderous 'kawakasaki' Mach 111 500's
the original one with the "$%#@&^*! what was that! power curve", and the weird
handling!
I eventually decided that 'bikes and I were not a good combo. I was a rock
climber from 14 and, I was also an infantryman at one time! (Grunt, grunt).
Girls didn't see you doing these things then.
But the 'soldiering' and 'bikes' came, LATER.
'Older' Oz Joenetters might remember a lady called Pat Firnman on TV, in an
early black and white local edition of
'Beauty and the Beast'. That was what 'she' looked like, but in school
uniform. The local CofE girls grammar school (Episcopalian in Nth Am) sent
some girls to join the cathedral choir I was in. I was 17. BAMMM!
I'm married, 20 years this June, two boys one soon 18, and I still turn around.
A Duke, famously wild in his younger days, was asked on his 100th birthday
whether he still enjoyed 'the ladies'. 'Ahem, Still enjoy noticing a trim
ankle, yes, .......... by jove, I'm damned if I can remember why!'
regards
Tim B
=========================================================================
From: Scott Walters <sfwalters@worldnet.att.net>
Subject: Re: [JN] fast motorbikes and chasing girls
Date: Wed, 01 Dec 1999 11:21:54 -0500
Source: Sound Digest Archive v02.n350
Tim,
I'll call your Bultaco with a Can-AM 250. Lots of fun, even in
snow! As for the Kawi 500 Triple mine was orange and I had a love
hate relationship with the "Wobble Demon Knob" on the triple tree. I
loved to try and figure out if it really helped and it hated being
messed with.
I also used to go rock climbing in Joshua Tree, Southern Cal and
still have some of the scars on my hands from it. I did this while in
the service of my country, USMC. I wasn't however a ground pounder.
I was an enlisted Crew Chief / Plane Captain on Sikorsky CH-53
helicopters all models A through E. Now with a wife who is a nurse
and three kids; two daughters and a son, I don't even own a rope and I
never go anywhere with less than four wheels.
Scott
Tim_Bailey@medibank.com.au wrote:
>
> A Bultaco 250 single (2stroke) sports racer and,
>
> one of those murderous 'kawakasaki' Mach 111 500's
> the original one with the "$%#@&^*! what was that! power curve", and the weird
> handling!
>
> I eventually decided that 'bikes and I were not a good combo. I was a rock
> climber from 14 and, I was also an infantryman at one time! (Grunt, grunt).
> Girls didn't see you doing these things then.
>
> But the 'soldiering' and 'bikes' came, LATER.
>
> 'Older' Oz Joenetters might remember a lady called Pat Firnman on TV, in an
> early black and white local edition of
> 'Beauty and the Beast'. That was what 'she' looked like, but in school
> uniform. The local CofE girls grammar school (Episcopalian in Nth Am) sent
> some girls to join the cathedral choir I was in. I was 17. BAMMM!
>
> I'm married, 20 years this June, two boys one soon 18, and I still turn around.
>
> A Duke, famously wild in his younger days, was asked on his 100th birthday
> whether he still enjoyed 'the ladies'. 'Ahem, Still enjoy noticing a trim
> ankle, yes, .......... by jove, I'm damned if I can remember why!'
>
> regards
> Tim B
=========================================================================
From: Scott Walters <sfwalters@worldnet.att.net>
Subject: Re: [JN] fast motorbikes and chasing girls
Date: Wed, 01 Dec 1999 17:17:49 -0500
Source: Sound Digest Archive v02.n350
Tim,
I'll call your Bultaco with a Can-AM 250. Lots of fun, even in
snow! As for the Kawi 500 Triple mine was orange and I had a love
hate relationship with the "Wobble Demon Knob" on the triple tree. I
loved to try and figure out if it really helped and it hated being
messed with.
I also used to go rock climbing in Joshua Tree, Southern Cal and
still have some of the scars on my hands from it. I did this while in
the service of my country, USMC. I wasn't however a ground pounder.
I was an enlisted Crew Chief / Plane Captain on Sikorsky CH-53
helicopters all models A through E. Now with a wife who is a nurse
and three kids; two daughters and a son, I don't even own a rope and I
never go anywhere with less than four wheels.
Scott
Tim_Bailey@medibank.com.au wrote:
>
> A Bultaco 250 single (2stroke) sports racer and,
>
> one of those murderous 'kawakasaki' Mach 111 500's
> the original one with the "$%#@&^*! what was that! power curve", and the weird
> handling!
>
> I eventually decided that 'bikes and I were not a good combo. I was a rock
> climber from 14 and, I was also an infantryman at one time! (Grunt, grunt).
> Girls didn't see you doing these things then.
>
> But the 'soldiering' and 'bikes' came, LATER.
>
> 'Older' Oz Joenetters might remember a lady called Pat Firnman on TV, in an
> early black and white local edition of
> 'Beauty and the Beast'. That was what 'she' looked like, but in school
> uniform. The local CofE girls grammar school (Episcopalian in Nth Am) sent
> some girls to join the cathedral choir I was in. I was 17. BAMMM!
>
> I'm married, 20 years this June, two boys one soon 18, and I still turn around.
>
> A Duke, famously wild in his younger days, was asked on his 100th birthday
> whether he still enjoyed 'the ladies'. 'Ahem, Still enjoy noticing a trim
> ankle, yes, .......... by jove, I'm damned if I can remember why!'
>
> regards
> Tim B
=========================================================================
From: "Daniel J. Marshall" <danmarshall@worldnet.att.net>
Subject: [JN] FA: TAD, Altec Drivers, Horns, SE Amps
Date: Fri, 16 Jun 2000 09:15:45 -0700
Source: Sound Digest Archive v02.n581
Hi All,
Good stuff on eBay, all in excellent condition.
.
Pair of TAD TD-2001 HF drivers
Pair of Altec H-808 tar-filled multi-cellular horns
Pair TAD 1601b 15" drivers
Pair of 12" Altec woofers
Pair of older 8" mid-bass drivers (I think they are JBLs)
Pair of tweaked Heath SE 6BQ5 amps
http://cgi6.ebay.com/aw-cgi/eBayISAPI.dll?ViewListedItems&userid=danmarshall@worldnet.att.net
OK, so I pussed out again (with regard to building larger enclosures,
just don't have the energy anymore).
Dan Marshall
=========================================================================
From: Dan Marshall <mdaniel7@uswest.net>
Subject: [JN] FA: TAD TL-1601 15" Woofer
Date: Fri, 14 Jul 2000 20:52:41 -0700
Source: Sound Digest Archive v02.n604
http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=381752164
=========================================================================
From: analogtubeaudio@t-online.de (Robert Graetke)
Subject: [JN] ***FA: Telefunken quad EL 34 (6CA7) NOS ***
Date: Fri, 03 Dec 1999 00:49:02 +0100
Source: Sound Digest Archive v02.n352
http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=211224511
=========================================================================
From: Power.Ralph@epamail.epa.gov
Subject: [JN] Father's Day present
Date: Mon, 11 Jun 2001 12:10:25 -0400
Source: Sound Digest Archive v02.n907
Hi All,
I just bought myself an early Father's Day present.
WalMart has a 6 disc and a 10 disc CD changer that plays through your
car radio (FM modulator) for $99.85 everyday, so take your pick. The 10
disc changer holds more CDs, but is physically larger, so check your
mounting places before choosing. I figured for $99, how could I go wrong.
I bought the 10 disc changer for my truck and had to mount it on the hump
since it wouldn't fit anywhere else. Looks OK, but not cool. Installation
was pretty easy after I figured out where I was going to mount it.
It's made in China (of course), and the changer mechanism seems fairly
robust, at least I haven't had any burps yet. The sound was a little harsh
at
first but seems to be mellowing out some now. There is an annoying
whistling
during quiet spots at low levels when the volume is very high, but at
normal
listening levels it's not audible. The whistle is there even when the
engine is
not running, so it's not the alternator.
But I'm really enjoying having lots of good, high fidelity tunes while I'm
driving,
so it's clearly a good present to me and well worth it.
My 2 cents,
Ralph Power
Computer Sciences Corp.
USEPA, Athens, GA
(706) 355-8410
=========================================================================
From: Rick Francis <rfrancis@glasscity.net>
Subject: [JN] FA: Transformers, including pair of UTC S-40
Date: Fri, 30 Jun 2000 22:53:02 -0400
Source: Sound Digest Archive v02.n593
I have 5 transformers (so far) for sale on ebay, and that includes a
pair of UTC S-40s. I'll add more stuff as I can, including pairs of
chokes and more power transformers. The baby needs shoes.
http://cgi6.ebay.com/aw-cgi/eBayISAPI.dll?ViewListedItems&userid=tubino
Thanks for the bandwidth,
Rick Francis
=========================================================================
From: Dan Marshall <mdaniel7@uswest.net>
Subject: [JN] FA: Tubes
Date: Mon, 11 Dec 2000 15:26:59 +0000
Source: Sound Digest Archive v02.n757
Hi All,
I have some tubes listed on eBay, closing in the next day or two. A Lab
matched pr of Mullard 6BQ5s, two very carefully matched pair of NOS
6B4Gs and some 6JE6/6LQ6s. Will likely list more later.
Dan Marshall
=========================================================================
From: AnnaLogg@aol.com
Subject: [JN] Faux pas . . .
Date: Tue, 23 Feb 1999 12:26:00 EST
Source: Sound Digest Archive v02.n057
In a message dated 2/23/99 10:45:25 AM Eastern Standard Time, Anna Logg wrote:
> things a 'gourmet' would relish: hors d'oeuvre (also, canape), a la mode (as
> in "pie a la mode"), croissant, l'aissez faire
*l'aissez faire* ??? Pardonnez moi, not something one eats <giggle!>. Meant to
put this under "political" expressions. (Probably was thinking of "eclair" .
. Mmmmm.)
Well, don't want to start another cause celebre . . . ;-)
Au revoir,
Anna
=========================================================================
From: "PEARL Cust Serv" <custserv@pearl-hifi.com>
Subject: Re: [JN] Faux pas . . .
Date: Tue, 23 Feb 1999 14:08:07 -0700
Source: Sound Digest Archive v02.n057
> In a message dated 2/23/99 10:45:25 AM Eastern Standard Time, Anna Logg wrote:
>
>> things a 'gourmet' would relish: hors d'oeuvre (also, canape), a la mode (as
>> in "pie a la mode"), croissant, l'aissez faire
>
> *l'aissez faire* ??? Pardonnez moi, not something one eats <giggle!>. Meant to
> put this under "political" expressions. (Probably was thinking of "eclair" .
> . Mmmmm.)
>
> Well, don't want to start another cause celebre . . . ;-)
>
> Au revoir,
> Anna
- ------------------------
Big fun. .
Murky buckets ! ! !
Bill - PEARL
=========================================================================
From: Daniel Normolle <monk@umich.edu>
Subject: [JN] Favorite Ellington
Date: Wed, 28 Apr 1999 09:38:02 -0400
Source: Sound Digest Archive v02.n134
In case you have trouble choosing a record to play tomorrow, I post my
list of favorite Ellington disks. Your mileage will certainly vary, as there
is so much to choose from:
Blanton-Webster Band
Black, Brown & Beige
Live at Fargo
Small Ellington Units
Such Sweet Thunder
Back to Back
Side by Side
Ellington & Coleman Hawkins
Ellington & Coltrane
1956 Newport Concert
Far East Suite
Ella's Ellington Songbook
Money Jungle
And His Mother Called Him Bill
Great Paris Concert
Duke's Big Four
This One's for Blanton
dpn
=========================================================================
From: "Phil Sieg" <psieg@nxs.net>
Subject: Re: [JN] Favorite Ellington
Date: Wed, 28 Apr 1999 10:38:45 -0400
Source: Sound Digest Archive v02.n134
Daniel,
Great list! May I add "Blues in Orbit" and "Ellington Indigos". But
really, we're talking Duke and it's almost impossible to go wrong.
Phil
- ----- Original Message -----
From: Daniel Normolle <monk@umich.edu>
To: <sound@io.com>
Sent: 28 April, 1999 09.38
Subject: [JN] Favorite Ellington
> In case you have trouble choosing a record to play tomorrow, I post my
> list of favorite Ellington disks. Your mileage will certainly vary, as
there
> is so much to choose from:
>
> Blanton-Webster Band
> Black, Brown & Beige
> Live at Fargo
> Small Ellington Units
> Such Sweet Thunder
> Back to Back
> Side by Side
> Ellington & Coleman Hawkins
> Ellington & Coltrane
> 1956 Newport Concert
> Far East Suite
> Ella's Ellington Songbook
> Money Jungle
> And His Mother Called Him Bill
> Great Paris Concert
> Duke's Big Four
> This One's for Blanton
>
> dpn
>
>
>
=========================================================================
From: Steve Berger <aprilsound@earthlink.net>
Subject: Re: [JN] Favorite Ellington OH LUCKY ME!
Date: Wed, 28 Apr 1999 10:22:09 -0400
Source: Sound Digest Archive v02.n134
Daniel Normolle wrote:
>
> In case you have trouble choosing a record to play tomorrow, I post my
> list of favorite Ellington disks. Your mileage will certainly vary, as there
> is so much to choose from:
>
> Blanton-Webster Band
> Black, Brown & Beige
> Live at Fargo
> Small Ellington Units
> Such Sweet Thunder
> Back to Back
> Side by Side
> Ellington & Coleman Hawkins
> Ellington & Coltrane
> 1956 Newport Concert
> Far East Suite
> Ella's Ellington Songbook
> Money Jungle
> And His Mother Called Him Bill
> Great Paris Concert
> Duke's Big Four
> This One's for Blanton
>
> dpn
Here in New York, WKCR is in the middle of a NINE DAY Ellington
tribute!! So, needless to say , Ellington is in the air!!!!!!!
Happy Birthday Duke
- --
Steve Berger <http://home.earthlink.net/~aprilsound/>
=========================================================================
From: "Chin See Ming" <chinseeming@hotmail.com>
Subject: [JN] Favorite power supply hook up wire
Date: Wed, 05 Apr 2000 16:41:47 PDT
Source: Sound Digest Archive v02.n511
Hi Joes:
I'm canvassing what you favor for power supply hook up wire and what's
available in the market. This would be for a preamp I'm putting together.
Right now, my choices seem to be hardware store multistranded house wire
(audiophile approval questionable) and Cardas large gauge litz wire
(difficult to work with?).
Any ideas would be much appreciated. I am assuming that the typical
audiophile signal hookup wire (Kimber, XLO, silver teflon etc.) would not be
appropriate from a safety point of view.
Ming
______________________________________________________
Get Your Private, Free Email at http://www.hotmail.com
=========================================================================
From: David Home <DHome@creo.com>
Subject: RE: [JN] Favorite power supply hook up wire
Date: Wed, 5 Apr 2000 23:05:05 -0700
Source: Sound Digest Archive v02.n511
I really like the Vampire Cast Copper wire from Michael Percy. Sounds good ,
6N purity I think and $0.15/ft for the 20 gauge size. Only drawback is that
it is enameled and is toughish to tin.
-----Original Message-----
From: Chin See Ming [mailto:chinseeming@hotmail.com]
Sent: Wednesday, April 05, 2000 4:42 PM
To: sound@lists.io.com
Subject: [JN] Favorite power supply hook up wire
Hi Joes:
I'm canvassing what you favor for power supply hook up wire and what's
available in the market. This would be for a preamp I'm putting together.
Right now, my choices seem to be hardware store multistranded house wire
(audiophile approval questionable) and Cardas large gauge litz wire
(difficult to work with?).
Any ideas would be much appreciated. I am assuming that the typical
audiophile signal hookup wire (Kimber, XLO, silver teflon etc.) would not be
appropriate from a safety point of view.
Ming
______________________________________________________
Get Your Private, Free Email at http://www.hotmail.com
=========================================================================
From: Tim_Bailey@medibank.com.au
Subject: [JN] Re: Favourite recordings
Date: Fri, 11 Aug 2000 16:16:13 +1000
Source: Sound Digest Archive v02.n624
chiming in a bit late
I decided to work from home for a few days it's getting to be shitfight here as
we approach the deathknell of Medibank Private Ltd, as it was. 25th August
Early music
the red book of monserrat - Jordi Savall
The art of courtly love - David Munrow
Medieval and renaissance instruments _ " ".
Baroque
Bach; A musical offering - the Leonhardt Consort
Montiverdi - Hyperion LP with Emma Kirkby and Rooley et al.
Bach: Mass in B Minor - Leonhardt, on HMu
Telemann- the Paris quartets - Bruggen (Teldec?)
Bach: Barndenburgs - Leonhardt Consort (RCA Seon)
Bach; Christams oratorio - HMu with the Tolz Boys Choir &Collegium Aureum (has
been reissued on CD).
Roccoco
CPE Bach - hamburg symphonies. Coll. Aur. HMU
CPE bach - keyboard music Leonhardt, Fp/harps/Clavichord. (double LP RCA Seon
?)
Classical:
on two Accent Lp's - Haydn -Cello/flute violin trios as published by Haydn -
(oiginally Baryton trios) with The Kuijken brothers!
Wieland, Barthold and Sigiswald -"tout ensemble" sheer joy, alas no flashin'
white teeth and choreography.
[some of god's classical chillun' hab got riddum too! ]
Mozarts Wind Serenades with the Danzi Quintet HMu, my Lp's are back issues (by
Quintessence USA).
Romantic and later:
Berlioz and Colin Davix on Philips esp. 'the symphony fantastic'
Elgar's Enigma variations, Monteux and the LSO? On Decca, a bargain 'World of
the great classics' reissue, and dead quiet for its age. That hall in London,
wow what a performance and from a Frenchman as well! [great bass extension test
rumble rumble from the underground!]
Jazz etc
Blossom dearie in melbourne esp. "I owe it all to my attorney bernie"
Ella and Satchmo doing 'porgy and bess songs' on Verve
her Duke Ellington Verve double LP..
An LP called 'The Gifted Ones', Ray brown, Dizzie and 'someone else' on piano!
A friend taped it for me on his Nak, now runs on my Nak.
Rock and roll
Stones
"get yer yayh yahs out"
"exile on main street"
"let it bleed"
Little feat
"little feat"
"waiting for columbus" on MFSL Superdisc vinyl.
Warmest
tim B
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=========================================================================
From: "Aaron Bohnen" <bohnen@unixg.ubc.ca>
Subject: [JN] FA: Wharfedale Denton 2 bookshelf speakers on Ebay...
Date: Sat, 30 Oct 1999 14:33:11 -0700
Source: Sound Digest Archive v02.n318
Hi everyone,
I just wanted to mention that in my continuing efforts to lighten my
audio load I am auctioning off a very nice little pair of classic
Wharfedale Denton 2 bookshelf speakers. Nice teak-veneered cabinets, 8"
cast woofers, 2" tweeters, good grilles, good binding posts, etc. etc.
If interested please have a look at:
http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=191122852
best regards to all and many thanks for the bandwidth,
Aaron
p.s. - I'm still trying to find a new home for an EV 12TRXB in fantastic
shape and a Goodmans Audiom 81 15" woofer.
___________________________________________________________
Aaron Bohnen email: bohnen@unixg.ubc.ca
- -Ph.D. Student, Civil Engineering Department, U.B.C.
- -website: http://www.civil.ubc.ca/home/bohnen
=========================================================================
From: TubeGarden@aol.com
Subject: [JN] FB and Beyond
Date: Wed, 22 Mar 2000 09:43:48 EST
Source: Sound Digest Archive v02.n490
Greets Jeets Neets!
My little one stage amp now has three intentional forms of feedback:
1. Degenerative, on the unbypassed portion (half) of the cathode resistors.
2. UL, from the CT of the OPT to the screen.
3. Positive, from above a 0.5 ohm resistor in the negative return wire of the
speaker, to the cathode.
_____
When I listen with my ears to real systems, I do not hear what my Teflon mind
expects. Often, it persuades me not to try something because it 'knows'
better.
I love my ears!
I hate my mind, sometimes.
Happy Ears!
Al B^}
=========================================================================
From: "P. de R. L." <triode@bow-tie.org.uk>
Subject: Re: [JN] FB and Beyond
Date: Wed, 22 Mar 2000 18:43:05 -0000
Source: Sound Digest Archive v02.n491
What a nice message!
Paul
- ----- Original Message -----
From: <TubeGarden@aol.com>
To: <sound@io.com>
Sent: Wednesday, March 22, 2000 2:43 PM
Subject: [JN] FB and Beyond
>
> Greets Jeets Neets!
>
> My little one stage amp now has three intentional forms of feedback:
>
> 1. Degenerative, on the unbypassed portion (half) of the cathode
resistors.
>
> 2. UL, from the CT of the OPT to the screen.
>
> 3. Positive, from above a 0.5 ohm resistor in the negative return wire of
the
> speaker, to the cathode.
>
> _____
>
> When I listen with my ears to real systems, I do not hear what my Teflon
mind
> expects. Often, it persuades me not to try something because it 'knows'
> better.
>
> I love my ears!
>
> I hate my mind, sometimes.
>
> Happy Ears!
> Al B^}
>
>
=========================================================================
From: Ishmael349@aol.com
Subject: Re: [JN] F&B grounds
Date: Tue, 1 Aug 2000 00:04:25 EDT
Source: Sound Digest Archive v02.n615
Dear Eric,
Absolutely, I'll look at your photos and send you a recording of my
observations. Just remember, I haven't built any amps in a few years. I am
however scheduled to build two in the next few months as I have two new
customers and need cash. You also have to remember two things: First - when
I was building amps, I was doing it 8-10 hours/day for almost five years. I
built more than 100. And at least two dozen preamps. Which means I lost a
lot of sleep and cried a lot of tears over parasitic oscillations. J.C.
always told me, "Welcome to the next level." Second - I have J.C. Morrison,
Kumoro, and Tommy Cadawas on my team. And on occasion, I enlisted the
services of the likes of Dick Sequera and John Curl. So I always had someone
to bail me out when I got in a jam. Sounds like you need a friend. I didn't
design an exceptional amplifier because I know a lot about electronics. My
amp is good because I have good taste. You have to know what your looking
for if your going to find it. I had a group of musical criteria and I did an
unbelievable amount of trial and error to get what I wanted. I spent four
years perfecting the Flesh & Blood and then sent it on a world tour to get
outside opinions. The only things I understand pretty good are filter theory
and maybe electro-magnetics. That being said, all audio should be built to
RF standards of grounding. I dodn't use point to point. I put all the parts
on 2" wide "tag strips" and used a star ground at the lowest signal point the
cathod of the input/voltage amplifier stage. This is where all grounds
should connect to the chassis. Try to keep all star ground wires nearly the
same length. Ground the heaters at this socket. I bend the heater ground
tab down at the 6SN7 socket and solder it directly to the copper ground
plane. And I put the 47,000uf cap on the 6SN7 tube socket. Try that. Or,
fasten (solder?) the copper RCA input jack directly to the copper (1/8"
thick) ground plane and use that as your star ground point. Send the photos
to Herbert Reichert, PO Box 50094, Staten Island, NY 10305. I'll reply on
mini-disc OK?
Good luck,
Herb
=========================================================================
From: evaguido <EvaGuido@iaehv.nl>
Subject: Re: [JN] F&B grounds
Date: Tue, 01 Aug 2000 23:26:11 +0200
Source: Sound Digest Archive v02.n616
dear Herb,
A star ground in my opinion is not a favourite sollution, as it
automatically leads to big loops (though it might work for low frequencies).
I wil present a short tutorial in Arhus, outlining a supply decoupling
concept.
Lateron, once there is some more time, I will rewrite that tutorial and
make it an article.
The concept is based on keeping currents local and minimising AC currents
throught the ground connection.
Once it is ready I'll put it somewere on the internet.
best regards
Guido
=========================================================================
From: "Hugh R Dean" <aspen@alphalink.com.au>
Subject: Re: [JN] F&B grounds
Date: Thu, 3 Aug 2000 07:50:35 +1000
Source: Sound Digest Archive v02.n616
Hi Guido,
You wrote this:
> A star ground in my opinion is not a favourite sollution, as it
> automatically leads to big loops (though it might work for low
frequencies).
>
> I wil present a short tutorial in Arhus, outlining a supply decoupling
> concept.
>
> Lateron, once there is some more time, I will rewrite that tutorial and
> make it an article.
This really caught my eye, because the importance of low noise floors is
crucial to proper performance and perception of dynamics. You really notice
this when the power supply uses quite diodes - particularly with sand
amplifiers.
Guido, I am particularly interested in this stuff because once any design is
fleshed out and built, earthing is usually the very last thing considered,
often forcing star earthing. I deeply regret not being at Arhus for your
presentation, and if you have any notes or ppt slides, please - please - put
me on your distribution. I could really learn from you!
Cheers,
Hugh R. Dean
Printed Electronics
Melbourne, Australia
=========================================================================
From: "PEARL Cust Serv" <custserv@pearl-hifi.com>
Subject: [JN] F/B & Phase Distortion, was - Worlds Cheapest OPT
Date: Mon, 05 Jun 2000 23:05:49 -0600
Source: Sound Digest Archive v02.n567
Hi, tube@jump.net wrote
> . . . . .but suffice it to say that Matti Otala
> proved many years ago that feedback absolutely cannot make distortions
> go away, it can only transform amplitude distortions into phase
> distortions.
Can you provide references here?
This is VERY interesting particularly since I just dreamed up a way of
measuring the phase of individual harmonic components as a function of both
swept frequency and stepped amplitude.
I've been wanting to do this for years and some recent hard study of
Richard Heyser finally booted me in the a** to think this thru.
So, Otala's work is very relevant at this point in my investigations,
particularly in view of the work I watched Meinter do a few years ago wrt
the audibility of jitter in digital circuitry. This is, after all, an
uncommonly pernicious form of phase distortion.
Tia . . . .
Best regards,
Bill - PEARL, Inc.
=========================================================================
From: "Dave Slagle" <dslagle@earthlink.net>
Subject: [JN] fc, meissner and other old stuff
Date: Sun, 21 May 2000 21:19:51 -0400
Source: Sound Digest Archive v02.n554
hey all.
i uploaded a page from the past to:
http://albums.photopoint.com/j/View?u=37049&a=237580&p=21498184&Sequence=0
its a bit weird to access... but give it a try... save it and print it
out... there is really a lot of stuff there....
field coils as chokes
the CT opposing choke of diagram C.... won't the dc cancel through the
opposing chokes on a common core? leaving the core to deal with the ac job
at hand...?? this one... in conjuntion with a phone call with a fellow joe
really has me thinking
the meissner pay per use supply of the 30's... note that the whole filter is
in the ground leg... very interesting... oh to be a fly on the wall of any
of these pre 30's thoughts... all we can do now is look back, study and
guess...
dave
=========================================================================
From: Dan Marshall <mdaniel7@uswest.net>
Subject: [JN] FD 78s
Date: Sun, 29 Apr 2001 11:39:15 +0000
Source: Sound Digest Archive v02.n876
Hi All,
I seem to recall some time back that some were interested in 78 rpm
records. I have a fair number in which I have no interest. If anyone
is interested, let me know and I will compose a list. They are mainly
classical.
Dan Marshall
=========================================================================
From: Tim_Bailey@medibank.com.au
Subject: Re: [JN] Fe 103's and V incarnation's.
Date: Mon, 24 Jan 2000 12:22:31 +1100
Source: Sound Digest Archive v02.n414
additional post re Fe 103's
Hi nick,
I have seven of these 4 0riginal cream cone brown surround jobs from the late
1970's plus 3 black cone ones from a MO/retail house here in Aus. they were a
disposal lot so that's it for now from them. The later ones were made in korea
but match physically ie externally. I also have two Taiwanese drivers with a
bigger magnet and claiming similar perf.
I have an article about putting the Fe 103, along with a choke based network, in
a v small ib box ,it was in one of the US's electroinics mags way back.
What are yr measured numbers for the FE103 cf the specs published by Fostex
(fromEiFL's site). I too have often thought about 'doing the dipole dance' with
an array of Fe103's. I even remember a 'phone rave to Allen wright about this
when he was still here in OZ, back in the 80's. Shades of a scrounger's
Porzilli array, but as a dipole. How many would you need to start getting real
sensitivity gains for tube amps (with 4/8/16 taps)?
Two of mine are in little very thick walled reflex boxes and have a network
using caps and resistors across the terminals, but no L. They run off a 4 ohm
baby pp bandpass sunwoofer, but i think nominall 4 ohm spkrs would match better
at the pasiive crossover point.
If I were using two Fe13's each in parallel, (4 ohms nominal) perhaps in one
of my two smaller 'spheres (Model 2's) what should I do to the values in th
network ie caps and resistors? I will send a diagram asap as yr answer will
prob depend on whether the caps and resistor are in series or parallel with each
other. (???)
I am also going to build a pr of rear spkrs soon for our little family room
'home theatre' and will use four salvaged cone tweeters, two per box wired out
of phase and crossed over as low as possible, to get pseudo dipole / 'diffuse'
effects. Angled facets for the tweeters, with one wide range 3-4inch on the
center baffle. I'll probably use the 'not-fosters' there.
[why????
well, I've recently obtained a s/h LuX home-theatre centre / add-on amp. I've
had it serviced, and a loop added, so that I can run a delay from, and then back
to, the main LRoom system. In the LRoom I'm going to use several small spkrs
dist'd around the room at a low spl and on delay. I'll use series-parallel
connections. Each ambience / 'incoherent' spkr will sit at the floor/wall
corner, facing up the wall at a 60 degree included angle. At first I'll just be
using several different salvaged 8 ohm drivers, but in the same type of angled
box. NB there was an article about this approach in spkr bldr ages back.]
If I can get some more FE103's, through Tandy here, or via the US, I will.
Tim B
****************************************************************
NOTICE - This message is intended only for the use of the
addressee named above and may contain privileged and
confidential information. If you are not the intended recipient
of this message you are hereby notified that you must not
disseminate, copy or take any action based upon it. If you
received this message in error please notify Medibank
Private Ltd immediately. Any views expressed in this
message are those of the individual sender, except where
the sender specifically states them to be the views of
Medibank Private Ltd.
****************************************************************
=========================================================================
From: Tim_Bailey@medibank.com.au
Subject: Re: [JN] Fe 103's and V incarnation's.
Date: Tue, 25 Jan 2000 09:15:14 +1100
Source: Sound Digest Archive v02.n416
****************************************************************
NOTICE - This message is intended only for the use of the
addressee named above and may contain privileged and
confidential information. If you are not the intended recipient
of this message you are hereby notified that you must not
disseminate, copy or take any action based upon it. If you
received this message in error please notify Medibank
Private Ltd immediately. Any views expressed in this
message are those of the individual sender, except where
the sender specifically states them to be the views of
Medibank Private Ltd.
****************************************************************
additional post re Fe 103's
Hi nick,
I have seven of these 4 0riginal cream cone brown surround jobs from the late
1970's plus 3 black cone ones from a MO/retail house here in Aus. they were a
disposal lot so that's it for now from them. The later ones were made in korea
but match physically ie externally. I also have two Taiwanese drivers with a
bigger magnet and claiming similar perf.
I have an article about putting the Fe 103, along with a choke based network, in
a v small ib box ,it was in one of the US's electroinics mags way back.
What are yr measured numbers for the FE103 cf the specs published by Fostex
(fromEiFL's site). I too have often thought about 'doing the dipole dance' with
an array of Fe103's. I even remember a 'phone rave to Allen wright about this
when he was still here in OZ, back in the 80's. Shades of a scrounger's
Porzilli array, but as a dipole. How many would you need to start getting real
sensitivity gains for tube amps (with 4/8/16 taps)?
Two of mine are in little very thick walled reflex boxes and have a network
using caps and resistors across the terminals, but no L. They run off a 4 ohm
baby pp bandpass sunwoofer, but i think nominall 4 ohm spkrs would match better
at the pasiive crossover point.
If I were using two Fe13's each in parallel, (4 ohms nominal) perhaps in one
of my two smaller 'spheres (Model 2's) what should I do to the values in th
network ie caps and resistors? I will send a diagram asap as yr answer will
prob depend on whether the caps and resistor are in series or parallel with each
other. (???)
I am also going to build a pr of rear spkrs soon for our little family room
'home theatre' and will use four salvaged cone tweeters, two per box wired out
of phase and crossed over as low as possible, to get pseudo dipole / 'diffuse'
effects. Angled facets for the tweeters, with one wide range 3-4inch on the
center baffle. I'll probably use the 'not-fosters' there.
[why????
well, I've recently obtained a s/h LuX home-theatre centre / add-on amp. I've
had it serviced, and a loop added, so that I can run a delay from, and then back
to, the main LRoom system. In the LRoom I'm going to use several small spkrs
dist'd around the room at a low spl and on delay. I'll use series-parallel
connections. Each ambience / 'incoherent' spkr will sit at the floor/wall
corner, facing up the wall at a 60 degree included angle. At first I'll just be
using several different salvaged 8 ohm drivers, but in the same type of angled
box. NB there was an article about this approach in spkr bldr ages back.]
If I can get some more FE103's, through Tandy here, or via the US, I will.
Tim B
=========================================================================
From: "John Hancock" <John_Hancock@swissre.com>
Subject: [JN] FE 103 Sigmas
Date: Wed, 7 Jul 1999 15:12:30 +0100
Source: Sound Digest Archive v02.n198
Tinno Christ wrote:
>I will be building a new pair Edgar Midrange horns, 200 Hz flare and
>10cm diameter round throat for my FE 103 Sigmas.
Hi Tinno,
I was wondering what your experience has been with the 103 Sigmas. I have
been toying with the idea of getting a pair due to their attractive price.
How do you have them set up, etc.? Do they make music? Thanks for your
insights,
John
=========================================================================
From: "J. Gordon Rankin" <waudio@cinti.net>
Subject: Re: [JN] FE 103 Sigmas
Date: Thu, 8 Jul 99 10:03:05 -0400
Source: Sound Digest Archive v02.n199
John,
>I was wondering what your experience has been with the 103 Sigmas. I have
>been toying with the idea of getting a pair due to their attractive price.
>How do you have them set up, etc.? Do they make music? Thanks for your
>insights,
First there is no 103 Sigmas only FE103 and FE108 Sigmas.
I have two 108 systems right now. I use the 108 from 200Hz in a sealed
chamber and a small 5" woofer. Makes for a great Monitor!
I also got a pair of the backhorns from Koji (Fostex part number BK10),
still in pieces will respond when I know something. I think it cost more
to ship thant the cabs cost.
Gordon
=======> Wavelength Audio <=======
mailto:waudio@cinti.net
http://www.WavelengthAudio.com
ph.fx. 513-271-4186 USA
=========================================================================
From: Michael Joncic <hit-me@netway.at>
Subject: Re: [JN] FE 103 Sigmas
Date: Fri, 09 Jul 1999 12:48:29 +0200
Source: Sound Digest Archive v02.n200
John worte:
Tinno Christ wrote:
>I will be building a new pair Edgar Midrange horns, 200 Hz flare and
>10cm diameter round throat for my FE 103 Sigmas.
Hi Tinno,
I was wondering what your experience has been with the 103 Sigmas. I have
been toying with the idea of getting a pair due to their attractive price.
How do you have them set up, etc.? Do they make music? Thanks for your
insights,
John
Hi John,
well, they are very nice sounding drivers for the money, just try it in a
small backloaded horn + a notch-filter and you'll see (hear, of course ;)
). plus for their size they are really efficient (91db/w/m i think). might
try a frontloaed horn sometimes, but there are other things to do first...
and gordon: there are 103 sigmas!!! (but i don't know of 108 sigmas?)
regards
mike
=========================================================================
From: "=?ISO-8859-1?Q?Torbj=F8rn_Lien?=" <mdrivekl@online.no>
Subject: Re: [JN] FE 103 Sigmas
Date: Fri, 9 Jul 1999 23:44:59 +0200
Source: Sound Digest Archive v02.n201
Hi all,-
I see there are some interest in the FE 103 sigmas
these days. I have played alittle with these some
time ago, and I don't think they are actually suitable
for fronthorn loading: They seem to lack the nescessary
encreasing (with frequency) response,-so I guess the
end result would turn out too "warm".
A back-loaded quarterwave horn,-or a reflex box would
be propriate,- the unit is, I guess, designed for
this type of operation.
The FE103 sigma can be sonically improved,-some time ago
I posted my experiences with venting of the enclosed air
behind centre-dome. Repeated below.
Regards
Torbjoern Lien
>
>
.......................[snip]
This unit was so nice that I put some labor into
it, trying to improve sound further, and with success.
Cause compared with other nice units. (The Axiom
80's, and some self-composed units , it suffered
from some hardness/edge in the midrange.
First I tried to remove the centre-dome.(Used
thinner to dissolve the rubber glue.) And the
sound *changed*...The hardness disappeared, but
sound higher up changed to the unpleasant,-and
the high end disappeared.I tried to damp the "hole"
above centre-pole with some thick felt, and I think
that helped some,-(I would have tried to make some
phase-plugs, but lacked proper tools.)But still lack
of high end.
So I figured that the domes had to go back, but that
unit needed some ventilation: I masked off the "inside"
v.c.gap-voicecoil former with papertape, used small
amounts of superglue to secure it without bonding the v.c.-former,
masked off whole driver, and from behind drilled
a hole (approx 9mm, or 1/3 +" dia) straight through the
centre-pole. This was infact quite easy, as the magnet-
system had a recessed spot in the middle were centre-pole
was "nitted" on.
So the hole came out in front precisely centered.I shaped
the hole in front of the pole with a "screw-rescess-drill
bit, and after cleaning away *all* the magnetic scrap from
the unit I unmummified it. Then I damped the remains of the
straight surface of the pole-piece with a ring of thick felt, glued the
dome back on, and tested it again.
I was abit concerned that I had ruined the magnetic flux-
density by doing this (as gentle as I managed,) and probably
some was lost,-Nonetheless,- The result was remarkable:
The unit sounded as before,-without the unpleasant edge in
the midrange. Hyper smooth. Treble was restored, and was
maybe even better than before the mod. And it could actually
be verified: Testing the unit with sine-waves in the 400-3000
khz gave an extremely airy, kind of no directional pleasant
presentation. Now,-by sticking a pencil up the drilled hole
through the centre-pole, closing ventilation off, and filling
up voulme behind the dome, the distinct marked edge to the
sound reappeared. So, by direct comparison, it was easy to
hear that the edge simply was distortion,- the sine + unpleasant, prob.
odd overtones.....
[snip]
>
>
>
>
>
=========================================================================
From: "Timo Christ" <tic@vossnet.de>
Subject: [JN] Re: FE 103 Sigmas
Date: Sat, 10 Jul 1999 00:12:42 +0200
Source: Sound Digest Archive v02.n201
Hello Gordon, Joes;
Gordon wrote:
> First there is no 103 Sigmas only FE103 and FE108 Sigmas.
Not True ! I personally own FE 103 Sigmas . They carry the ACR label
but that's for all Fostex hifi speakers in Germany.
The Shop where i bought them also has FE 103 .
FE 103 - 59 DM
FE 103 Sigma - 84 DM
They differ in magnet size, diaphragm and suspension (visibly).
FWIW,
Timo
Timo Christ
tic@vossnet.de
the hifi-DIY mailing list @ www.onelist.com
Go for the Glow - ... LED VU METERS !!! :-)
=========================================================================
From: vegchelp@iaehv.nl (Peter van Vegchel)
Subject: Re: [JN] FE 103 Sigmas
Date: Tue, 13 Jul 1999 20:34:35 +0200 (CEST)
Source: Sound Digest Archive v02.n204
Hi Guys,
A related question:
I've seen an announcement of a new Fostex type at the Japanese site,
www.fostex.co.jp, in the what's new section.
It's a 4inch fullrange, 6N... something, it has a moving mass of only 1.3grams,
about half of a FE103/108. From the picture, using a little bit of imagination,
I see a small phase plug...
My problem (and I guess a lot of people) is that the whole site is in japanese.
Do we have any japanese people on the list who could translate the few lines
of specifications and tell me were I could order them. I tried Koji but he
didn't
respond.
PS, I've used the FE103, FE103Sigma and the FE108 Sigma, all in a backloaded
horn, which can be seen at Tom Dunkers page.
And I must say a hear some nastiness in the midrange also, I think it's
time for
some modification. Thanks for the ideas guys.
regards, Peter
>Hi all,-
>
>I see there are some interest in the FE 103 sigmas
>these days.
=========================================================================
From: "J. Gordon Rankin" <waudio@cinti.net>
Subject: Re: [JN] FE 103 Sigmas
Date: Thu, 8 Jul 99 10:03:05 -0400
Source: Sound Digest Archive v02.n209
John,
>I was wondering what your experience has been with the 103 Sigmas. I have
>been toying with the idea of getting a pair due to their attractive price.
>How do you have them set up, etc.? Do they make music? Thanks for your
>insights,
First there is no 103 Sigmas only FE103 and FE108 Sigmas.
I have two 108 systems right now. I use the 108 from 200Hz in a sealed
chamber and a small 5" woofer. Makes for a great Monitor!
I also got a pair of the backhorns from Koji (Fostex part number BK10),
still in pieces will respond when I know something. I think it cost more
to ship thant the cabs cost.
Gordon
=======> Wavelength Audio <=======
mailto:waudio@cinti.net
http://www.WavelengthAudio.com
ph.fx. 513-271-4186 USA
=========================================================================
From: "=?ISO-8859-1?Q?Torbj=F8rn_Lien?=" <mdrivekl@online.no>
Subject: Re: [JN] FE 103 Sigmas
Date: Mon, 26 Jul 1999 11:34:21 +0200
Source: Sound Digest Archive v02.n212
J. Gordon Rankin <waudio@cinti.net> wrote:
> First there is no 103 Sigmas only FE103 and FE108 Sigmas.
>
There i s (atleast was) a FE103Sigma. I have 4 of them.
If my memory is right, the FE103 has a smaller
magnet and plain halve-roll cloth surround. Whereas the
Sigma has a pleated accordion surround and the bigger
magnet. Don't know about possible differences in diaphragm/voicecoil.
Regards
Torbjoern lien
>
>
>
=========================================================================
From: "Carter Hendricks" <carter@i1.net>
Subject: [JN] FE 208 ES
Date: Fri, 11 Feb 2000 23:03:49 -0600
Source: Sound Digest Archive v02.n445
Here are some nice photos of the
beautiful FE208ES and what about
the other one, at the bottom of the
page???
--Carter
http://www2.plala.or.jp/takatsugu/sub7.htm
=========================================================================
From: TubeGarden@aol.com
Subject: Re: [JN] FE 208 ES
Date: Sat, 12 Feb 2000 00:47:49 EST
Source: Sound Digest Archive v02.n445
In a message dated 2/11/00 10:11:08 PM US Mountain Standard Time,
carter@i1.net writes:
> the other one
Hi Carter, well, the fw-800n is the fostex 31.5 " woofer,
do not know the other twoo listed, but would like to :-)
Happy Ears!
Al
PS time test test drive Duncan's PSUD2
=========================================================================
From: "Timo Christ" <tic@vossnet.de>
Subject: [JN] FE208S Jericho Horn
Date: Thu, 7 Oct 1999 21:37:22 +0200
Source: Sound Digest Archive v02.n295
Hello All,
As promised to some of you I will try to describe how Fostex FE 208
sigma sound in the K+T Jericho horn.
Today I listened to a variety of music in my brother's listening
room. It's kind of a weird room (under the roof), one speaker is in a
room corner and the other one not.. well.
First I was severely disappointed by the bass but then i moved around
the room and found a perfect spot, in the near field about 1 m in
front of the speakers (app. 1,50m away from each FE208). In this spot
bass response was *perfect*, deep/low, impact, dynamic and clear.
Midrange was clean and impressively dynamic right from the start but
too harsh, i suffered "listener fatigue" after a short while.
This was "corrected" by the "Presence" tone control on my bro's
Grundig amp (solid state, PP, BJT). Klang und Ton published a passive
correction network to get rid of this midrange harshness but we chose
to not build it.
I liked the FE208S' highrange presentation being realistic and clean
and right in level.
Oh well i hate to describe sound in words....
see ya later,
Timo
Timo Christ
tic@vossnet.de
the hifi-DIY mailing list @ www.onelist.com
horn page: http://pages.vossnet.de/tic/hornfolds.html
=========================================================================
From: "Holger Stein" <steinmusic@cityweb.de>
Subject: Re: [JN] FE208S Jericho Horn
Date: Fri, 8 Oct 1999 10:03:20 +0200
Source: Sound Digest Archive v02.n295
Hi Hugh, Hi Timo
Like all fullrange speakers also the FE 208 comes a big step forward using
C37 Speziallack. Uwe Kähler, who made the prototypes of the horns for K&T,
also used C37 Speziallack. He, and some of our customers who built this horn
are very lucky about the results.
Best regards
Holger Stein
xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Stein Hifi Systems
Scharpenberg 64a
45468 Mülheim
Germany
Tel.: ++49 208 32089
Fax ++49 208 381890
e-mail info@steinmusic.de
URL: http:// www.steinmusic.de
Worldwide distributor for Ennemoser's C37 Lack
..and much more
- ----- Original Message -----
From: Hugh R. Dean <aspen@alphalink.com.au>
To: Timo Christ <tic@vossnet.de>; Joenet <sound@deliverator.io.com>
Sent: Friday, October 08, 1999 3:41 AM
Subject: Re: [JN] FE208S Jericho Horn
> Hi Timo,
>
> I have a pair of Jericho horns with unequalised Fostex 208 sigmas. This
> combination is highly efficient; I believe about 102dB/watt/metre.
> However, as a full range driver using powerful magnet and stiff paper, it
> has noticeable peaks and troughs in its delivery and a Lowther-like peak
at
> around 4KHz. It really needs the right amp otherwise you feel you are in
> the presence of Mme Guillotine.
>
> The cone is very stiff, giving very high mechanical damping. Thus it
sounds
> pretty dead with a SS amplifier. However, with a decent tube amp (211 or
> 300B monoblocks, Leak TL12) the sound is sensational, particularly on
female
> vocals, giving that 'smoke filled nightclub' atmosphere which features so
> brilliantly on old Sarah Vaughan tracks.
>
> The bass is, as you say, very room dependent, but there is a satisfaction
in
> it not possible with conventional three way approaches. My understanding
is
> that it is 6dB down at 32 Hz.
>
> I do not have an all tube amplifier and consequently I cannot enjoy these
> speaks as I would like. However, I am about to build a SET 811-3, so I
> guess I will soon find out.
>
> Cheers,
>
> Hugh R. Dean
> Melbourne, Australia
>
>
=========================================================================
From: "Hugh R. Dean" <aspen@alphalink.com.au>
Subject: Re: [JN] FE208S Jericho Horn
Date: Fri, 8 Oct 1999 11:41:30 +1000
Source: Sound Digest Archive v02.n295
Hi Timo,
I have a pair of Jericho horns with unequalised Fostex 208 sigmas. This
combination is highly efficient; I believe about 102dB/watt/metre.
However, as a full range driver using powerful magnet and stiff paper, it
has noticeable peaks and troughs in its delivery and a Lowther-like peak at
around 4KHz. It really needs the right amp otherwise you feel you are in
the presence of Mme Guillotine.
The cone is very stiff, giving very high mechanical damping. Thus it sounds
pretty dead with a SS amplifier. However, with a decent tube amp (211 or
300B monoblocks, Leak TL12) the sound is sensational, particularly on female
vocals, giving that 'smoke filled nightclub' atmosphere which features so
brilliantly on old Sarah Vaughan tracks.
The bass is, as you say, very room dependent, but there is a satisfaction in
it not possible with conventional three way approaches. My understanding is
that it is 6dB down at 32 Hz.
I do not have an all tube amplifier and consequently I cannot enjoy these
speaks as I would like. However, I am about to build a SET 811-3, so I
guess I will soon find out.
Cheers,
Hugh R. Dean
Melbourne, Australia
=========================================================================
From: "J. Gordon Rankin" <waudio@cinti.net>
Subject: Re: [JN] FE208S Jericho Horn
Date: Fri, 8 Oct 99 09:48:30 -0400
Source: Sound Digest Archive v02.n296
Timo, Gang;
I found that because of the qt (similar problem with lowthers) is that
the horn could not be optimized for really low bass. I made a 40Hz
backhorn for the 208 and it worked well. I did not have nay midrange
augmentation as described (I guess I could not read it, assumed since
there was a filter) in the Gerico literature.
I found the Sigma 164 to be a better overall winner in the Fostex line
for backhorn. Too bad the cabinets have to be so... overwhelming.
>I have a pair of Jericho horns with unequalised Fostex 208 sigmas. This
>combination is highly efficient; I believe about 102dB/watt/metre.
>However, as a full range driver using powerful magnet and stiff paper, it
>has noticeable peaks and troughs in its delivery and a Lowther-like peak at
>around 4KHz. It really needs the right amp otherwise you feel you are in
>the presence of Mme Guillotine.
Hugh, the Fostex's are 96.5dB/97dB, also the peak appears to be in the
design of the horn. If the horn has a heavy turn, the reflection seems to
add to the front output.
I have the 208 in a ported box right now, very flat to about 10KHz
(actually higher but still need something up top).
Gordon
=======> Wavelength Audio <=======
mailto:waudio@cinti.net
http://www.WavelengthAudio.com
ph.fx. 513-271-4186 USA
=========================================================================
From: "J. Gordon Rankin" <waudio@cinti.net>
Subject: [JN] FE87 line source, baffle or otherwise QT=1.04 help
Date: Tue, 22 Feb 00 17:48:54 -0500
Source: Sound Digest Archive v02.n459
Gang,
I got to thinking after reading Tom's post about his FE87 backhorns.
My baffle idea is itching up again, to remind:
9 FE87's in series parallel (3 in par, 3 set's in series): 8 ohms 95dB
flat 150-20K -3dB
10-12" Woofer in a sub box.
The only reason I say baffle is the high Q of this speaker: Qt=1.04, Vas
about 1L.
If some of you plugged in the numbers, 1 driver in a 400L box will get
you about 20Hz.
Well of course it does not figure...
Any ideas, help or observations?
Gordon
=====> Wavelength Audio <=====
mailto:waudio@cinti.net
http://www.WavelengthAudio.com
ph.fx. 513-271-4186 USA
=========================================================================
From: bobcx@earthlink.net
Subject: Re: [JN] FE87 line source, baffle or otherwise QT=1.04 help
Date: Wed, 23 Feb 2000 12:35:50 -0500
Source: Sound Digest Archive v02.n460
- ----- Original Message -----
From: J. Gordon Rankin <waudio@cinti.net>
To: Sound Practices MAIL LIST <sound@lists.io.com>
Sent: Tuesday, February 22, 2000 5:48 PM
Subject: [JN] FE87 line source, baffle or otherwise QT=1.04 help
> Gang,
>
> I got to thinking after reading Tom's post about his FE87 backhorns.
>
> My baffle idea is itching up again, to remind:
>
> 9 FE87's in series parallel (3 in par, 3 set's in series): 8 ohms 95dB
> flat 150-20K -3dB
> 10-12" Woofer in a sub box.
I thought this was an excellent idea when you first mentioned it. I think
this has the potential of being a killer system which would not be too
difficult to duplicate.
Bob
=========================================================================
From: evaguido <EvaGuido@iaehv.nl>
Subject: [JN] Feedback
Date: Thu, 04 May 2000 22:15:58 +0200
Source: Sound Digest Archive v02.n539
hi all,
Recently I sent an E-mail considering feedback, and two different
mechanisms that I distinct. I statd them in Dutch as I didn't know the
exact translation.
They are
1-terugkoppeling (feedback)
2-terugwerking
An example of "1" is rather easy, just take the classic feedback from
output to input as an example.
For "2" a typical example is the following:
Take a triode and apply heater, anode and negative grid voltage. As a
result a certain cirrent will run.
Now change the anode voltage; The current will change. It is a typical
example of what happens with a gain circuit containing impedance in the
anode. This to me falls in that category "2".
Anyone agrees on my fundamental distinction ? Could anyone give a decent
translation ?
Have fun
Guido
Now
At 10:15 04/05/2000 -0400, jc morrison wrote:
>
>
>"T. Loesch" wrote:
>
>> Hi there,
>>
>> >Tell that to the people putting ferrites on interconnects!
>>
>> Darryl, there is acrucial difference here. The Grid of a small signal Valve
>> is as close to an "infinite" Impedance as you will ever get.
>
>hey thorsten,
>this is what i was suggesting needed a little more depth... the input
impedance
>of a small signal triode is most definitely a *finite* thing. other than
>myself, anyone who has had to hack, repair or design a vhf radio can tell you
>this... especially in a triode capable of working into the low gigahz
range. it
>becomes more and more *finite* as you go up in frequency. again, and this is
>only a suggestion, because of the very *finite* capacitances and inductances
>that go along with building a triode amplifier in the real world, and the
>resonances and un-damped oscillatory behavior which are an integral part
of the
>actual environment, it might help someone struggling, to understand why. i
>think it would be fabulous and really chic if "equivalent" circuits really
>were... for those who are having a hard time getting their gadgets up and
>running, the stuff the models leave out or just plain and simple can't
account
>for, can also make or break a weekend, or at least a mood or a soda can.
if you
>consider opamps, for a minute, and the various input currents required for
>different models to work at video frequencies, or at digital frequencies, why
>would it shock you to discover that small signal tubes might share this
>characteristic? i'm sure you've held your breath or cursed out loud when
stuff
>you're working on explodes or makes nothing but pulses at 50mhz (and glows
>pretty purple). i learn every time something goes wrong, and i have been very
>fortunate in this department. anyway, ferrite beads are cute.
>jc
>
>
>
>
=========================================================================
From: tube@jump.net
Subject: Re: [JN] Feedback
Date: Thu, 04 May 2000 23:06:37 -0500
Source: Sound Digest Archive v02.n539
evaguido wrote:
> hi all,
>
> Recently I sent an E-mail considering feedback, and two different
> mechanisms that I distinct. I statd them in Dutch as I didn't know the
> exact translation.
>
> They are
>
> 1-terugkoppeling (feedback)
> 2-terugwerking
>
> An example of "1" is rather easy, just take the classic feedback from
> output to input as an example.
>
> For "2" a typical example is the following:
>
> Take a triode and apply heater, anode and negative grid voltage. As a
> result a certain cirrent will run.
>
> Now change the anode voltage; The current will change. It is a typical
> example of what happens with a gain circuit containing impedance in the
> anode. This to me falls in that category "2".
>
> Anyone agrees on my fundamental distinction ? Could anyone give a decent
> translation ?
>
I can tell you my basic, simple view of feedback; grab the output,
whatever it is--plate for the normal configuration, cathode for a
cathode follower--and move it. If the CONTROL voltage changes,
which in a tube is the grid-cathode voltage, then you have feedback,
period. Conversely, if the control voltage does not change, which it
doesn't in your "category 2", then you do not have feedback.
This is one of the other big advantages of tubes over solid-state.
A transformer coupled triode has a low output impedance due to its
low plate impedance, no "real" feedback needed. It is the ONLY amp
capable of doing so, except for Steve's "inverted triode" amp. All
solid state amps whatsoever, all claims to the contrary
notwithstanding, use feedback to get low output impedances. Threshold's
Stasis amps? I've seen the circuit, it uses massive feedback. Bedini
"zero-feedback amp"? I've seen the amp itself; massive feedback. Now,
I agree that cathode follower or emitter follower feedback is not
quite the same thing as other standard feedback schemes, because the
gm, or "amps per volt", plays a role. But it IS feedback, period. The
only possible exception, which I have never seen used, is the "power
j-fet". These remarkable devices have outputs that look EXACTLY like
a triode's, except that the "plate" impedance is 2 ohms! No transformer
needed, and no feedback either. I can't find them anywhere, however,
and they may even be extinct.
To summarize, your category 2 feedback is what I would call "output
impedance". I suspect that in your language the two categories are
considered to be very different things! Which is how I feel about
them.
Phil
=========================================================================
From: "Le Cleac'h J.-M." <lecleach@cgi.ensmp.fr>
Subject: Re: [JN] Feedback
Date: Fri, 5 May 2000 08:58:05 +0200
Source: Sound Digest Archive v02.n539
- ----------
> De : tube@jump.net
> A : evaguido <EvaGuido@iaehv.nl>
> Cc : sound@lists.io.com
> Objet : Re: [JN] Feedback
> Date : vendredi 5 mai 2000 06:06
> This is one of the other big advantages of tubes over solid-state.
> A transformer coupled triode has a low output impedance due to its
> low plate impedance, no "real" feedback needed. It is the ONLY amp
> capable of doing so,
Hello
While based on a real thing: triodes possess lower impedance than pentodes.
Your demonstration only applies when the load itself see its impedance
changing.(Power amplifier loading loudspeakers)
If the impedance is kept constant as in a 600ohms input there is no
advantage (except distortion spectrum) to use a triode over a pentode.
> The
> only possible exception, which I have never seen used, is the "power
> j-fet". These remarkable devices have outputs that look EXACTLY like
> a triode's, except that the "plate" impedance is 2 ohms! No transformer
> needed, and no feedback either. I can't find them anywhere, however,
Sony use to manufacture those power Vfets 15 years ago or so. There was
complementary P and N Vfets. I remember a Sony amplifier that used those
Vfets.
For what it seems some low power Vfets still exist (even if not still
manufactured). I saw in a paper in MJ a pramplifier that uses such Vfet in
a SRPP stage. (If memory serves the reference is something like 2SK63)
Best regards,
Jean-Michel Le Cleac'h, Paris, France
(leaving Paris for one week...)
=========================================================================
From: "Daniel J. Marshall" <danmarshall@worldnet.att.net>
Subject: Re: [JN] Feedback
Date: Fri, 05 May 2000 09:13:43 -0700
Source: Sound Digest Archive v02.n540
> Sony use to manufacture those power Vfets 15 years ago or so.
> There was complementary P and N Vfets. I remember a Sony amplifier
> that used those Vfets.
>
> For what it seems some low power Vfets still exist (even if not
> still manufactured). I saw in a paper in MJ a pramplifier that
> uses such Vfet in a SRPP stage. (If memory serves the reference
> is something like 2SK63)
>
> Best regards,
>
> Jean-Michel Le Cleac'h
Hi All,
Say, I have a Yamaha B-1 basic power amp that uses V Fet outputs (2SK77s
mfg by Yamaha, so they say in the service manual), a big bruser of an
amp weighing some 92 lbs. It has one dead channel, quite possibly bad
opt devices, though I have not checked it out. Does anyone happen to
have any such devices, or know where they can be bought. It alsop uses
several other V FET devices
I have never seen a more complex amp, it uses 39 FETS, 113 transistors,
3 LEDs, 64 diodes and 7 Zeners. That ought to be enough parts to really
screw up the sound. Perhaps I should listen to the operable channel to
see how it sounds.
Dan Marshall
=========================================================================
From: tube@jump.net
Subject: Re: [JN] Feedback
Date: Fri, 05 May 2000 10:31:34 -0500
Source: Sound Digest Archive v02.n540
"Le Cleac'h J.-M." wrote:
>
> > This is one of the other big advantages of tubes over solid-state.
> > A transformer coupled triode has a low output impedance due to its
> > low plate impedance, no "real" feedback needed. It is the ONLY amp
> > capable of doing so,
>
> Hello
>
> While based on a real thing: triodes possess lower impedance than pentodes.
> Your demonstration only applies when the load itself see its impedance
> changing.(Power amplifier loading loudspeakers)
>
> If the impedance is kept constant as in a 600ohms input there is no
> advantage (except distortion spectrum) to use a triode over a pentode.
That's a good point. Put a 600 ohm resistor across something with even
infinite output impedance, and you still get 600 ohms out with no
feedback. I suppose you could even do this with a pentode power amp,
putting 2000 ohms from plate to ground (with an 8K transformer), and
still get 2 ohms out to the speaker. Of course, the 2000 ohm resistor
would use 4 times as much power as the speaker, which it would also
steal from the speakers--for every 10 watts from the tube, just 2 W
would reach the speaker--but it could be done. However, when it comes
to power amps, one can see why all solid state manufacturers and most
pentode amps use feedback instead. (By the way, it was the Threshold
current-mirror amps, not the Stasis that I mentioned in the previous
post, which claimed "zero-feedback".)
> > The
> > only possible exception, which I have never seen used, is the "power
> > j-fet". These remarkable devices have outputs that look EXACTLY like
> > a triode's, except that the "plate" impedance is 2 ohms! No transformer
> > needed, and no feedback either. I can't find them anywhere, however,
>
> Sony use to manufacture those power Vfets 15 years ago or so. There was
> complementary P and N Vfets. I remember a Sony amplifier that used those
> Vfets.
>
> For what it seems some low power Vfets still exist (even if not still
> manufactured). I saw in a paper in MJ a pramplifier that uses such Vfet in
> a SRPP stage. (If memory serves the reference is something like 2SK63)
>
> Best regards,
>
> Jean-Michel Le Cleac'h, Paris, France
> (leaving Paris for one week...)
So they do exist! Now if I can only figure out how to get a few ...
I wonder if anyone actually made a zero-feedback solid state amp out
of them (preferably single-ended!), and then published an article on
the results. I still think that tubes would sound better, due to:
(1) No changes in output due to changes in recently dissipated power.
(2) No low quality parallel silicon capacitors.
(3) The ability to use small, high impedance, high quality caps in the
power supply which then get transformed to low impedance by the
transformer.
But, like triodes, it would NOT need feedback to have low output
impedance. Most of the advantage that triodes have over pentodes may
be due to their freedom from feedback. A power J-Fet amp would have
this same advantage, which means that it might come in a close second
to tube amps, maybe even to triode amps, for a fraction of the cost.
Besides, it would be so cool ...
Phil
=========================================================================
From: evaguido <EvaGuido@iaehv.nl>
Subject: Re: [JN] Feedback
Date: Fri, 05 May 2000 17:53:46 +0200
Source: Sound Digest Archive v02.n540
Phil, others
I wrote:
>> For "2" a typical example is the following:
>>
>> Take a triode and apply heater, anode and negative grid voltage. As a
>> result a certain cirrent will run.
>>
>> Now change the anode voltage; The current will change. It is a typical
>> example of what happens with a gain circuit containing impedance in the
>> anode. This to me falls in that category "2".
>>
>> Anyone agrees on my fundamental distinction ? Could anyone give a decent
>> translation ?
and you responded:
>I can tell you my basic, simple view of feedback; grab the output,
>whatever it is--plate for the normal configuration, cathode for a
>cathode follower--and move it. If the CONTROL voltage changes,
>which in a tube is the grid-cathode voltage, then you have feedback,
>period.
agreed
>Conversely, if the control voltage does not change, which it
>doesn't in your "category 2", then you do not have feedback.
but something else (regardless of how you call it)
>This is one of the other big advantages of tubes over solid-state.
>A transformer coupled triode has a low output impedance due to its
>low plate impedance, no "real" feedback needed.
And why does the triode have such low plate impedance ?
>It is the ONLY amp
>capable of doing so, except for Steve's "inverted triode" amp. All
>solid state amps whatsoever, all claims to the contrary
>notwithstanding, use feedback to get low output impedances.
If my category "2" is not considered to be feedback: Yes
>Threshold's
>Stasis amps? I've seen the circuit, it uses massive feedback. Bedini
>"zero-feedback amp"? I've seen the amp itself; massive feedback. Now,
>I agree that cathode follower or emitter follower feedback is not
>quite the same thing as other standard feedback schemes, because the
>gm, or "amps per volt", plays a role. But it IS feedback, period.
By definition, due to the (near)unity gain. By the way: also in follower
the mechanism under "2" plays a role !
>The
>only possible exception, which I have never seen used, is the "power
>j-fet". These remarkable devices have outputs that look EXACTLY like
>a triode's, except that the "plate" impedance is 2 ohms!
Wow !
>No transformer
>needed, and no feedback either. I can't find them anywhere, however,
>and they may even be extinct.
Which might be the reason you cant'find them..........
>To summarize, your category 2 feedback is what I would call "output
>impedance".
The impedance has its impact on the mechanism but I would not like to call
it like that
>I suspect that in your language the two categories are
>considered to be very different things! Which is how I feel about
>them.
OK
Thanks for your response though I am not yet satisfied....
Have fun and stay aware of the effects within category "2" !!!!!
regards
Guido
>Phil
>
>
>
>
=========================================================================
From: tube@jump.net
Subject: Re: [JN] Feedback
Date: Fri, 05 May 2000 23:35:45 -0500
Source: Sound Digest Archive v02.n540
evaguido wrote:
> Phil, others
[Snip]
>
> >Conversely, if the control voltage does not change, which it
> >doesn't in your "category 2", then you do not have feedback.
>
> but something else (regardless of how you call it)
>
> >This is one of the other big advantages of tubes over solid-state.
> >A transformer coupled triode has a low output impedance due to its
> >low plate impedance, no "real" feedback needed.
>
> And why does the triode have such low plate impedance ?
>
> >It is the ONLY amp
> >capable of doing so, except for Steve's "inverted triode" amp. All
> >solid state amps whatsoever, all claims to the contrary
> >notwithstanding, use feedback to get low output impedances.
>
> If my category "2" is not considered to be feedback: Yes
Well, I'm not sure I understand your question. A triode has low
impedance because the plate physically attracts the electrons, and the
grid has to "fight", so to speak, to stop them. I guess the real
characteristic of a triode is that the grid does not have complete
control over the current. With a pentode or transistor, the plate or
collector simply has no, or at least very little, control. A power
J-fet also has a "straight path" for the electrons to move, with gates
on either side, just like a grid, which have to fight to close off the
electron path. It's an inherent feature of the design.
Anyway, to feedback. You are right that the "type 2" feedback should
be called something. Maybe this is one of those cases where we get
used to thinking about things a certain way, and nothing else makes
sense. I have a hard time thinking of it as anything except the output
impedance characteristic of the device in question. For one thing, a
low output impedance can be simulated simply by placing a resistor in
parallel with the load. Is this feedback? It is similar to feedback in
that it "fights" to hold the load stable--but then, so does a battery.
Feedback, to my mind, MUST contain a "return to an earlier point", the
control voltage prior to the output. Because it returns to an earlier
point, it contains a delay, which in turn can be used to create
oscillation. A "real" low output impedance cannot do this.
In a real sense, feedback "imitates" a low output impedance. Matti
Otala did a thorough analysis of feedback after a discussion among
several people in "The Audio Critic", and apparently proved that
negative feedback ALWAYS transforms amplitude distortions into phase
distortions. I haven't read the paper, and wouldn't understand it if
I did, but my instincts tell me that the "there aint no free lunch"
conclusion of this paper is dead accurate. If you are careful, I
think that a fair amount of feedback can be tolerated, at least up
to the point where the ear starts noticing the increased phase
distortion, but I suspect that that's it. Triodes don't need any,
any they sound better than anything else. I am willing to bet good
money that no feedback is the big reason why. Of course, I tend to
lose good money, so ... (I am also going to respectfully disagree
with jcarr on this one, although I am sure he also knows way more
about electronics than I do).
As long as we understand the differences between the two mechanisms,
I suspect that we can call them almost anything and it won't matter.
To simply declare that it "is output impedance", now that I think
about it, is stupid. That is how I look at it, but it has several
effects, and it is the effects that matter, not the name. If type 2
feedback brings to mind those effects, then that is what you should
call it.
Phil
=========================================================================
From: tube@jump.net
Subject: [JN] Feedback
Date: Fri, 05 May 2000 23:37:14 -0500
Source: Sound Digest Archive v02.n540
tube@jump.net wrote:
> "Daniel J. Marshall" wrote:
>
> > > Sony use to manufacture those power Vfets 15 years ago or so.
> > > There was complementary P and N Vfets. I remember a Sony amplifier
> > > that used those Vfets.
> > >
> > > For what it seems some low power Vfets still exist (even if not
> > > still manufactured). I saw in a paper in MJ a pramplifier that
> > > uses such Vfet in a SRPP stage. (If memory serves the reference
> > > is something like 2SK63)
> > >
> > > Best regards,
> > >
> > > Jean-Michel Le Cleac'h
> >
> > Hi All,
> >
> > Say, I have a Yamaha B-1 basic power amp that uses V Fet outputs (2SK77s
> > mfg by Yamaha, so they say in the service manual), a big bruser of an
> > amp weighing some 92 lbs. It has one dead channel, quite possibly bad
> > opt devices, though I have not checked it out. Does anyone happen to
> > have any such devices, or know where they can be bought. It alsop uses
> > several other V FET devices
> >
> > I have never seen a more complex amp, it uses 39 FETS, 113 transistors,
> > 3 LEDs, 64 diodes and 7 Zeners. That ought to be enough parts to really
> > screw up the sound. Perhaps I should listen to the operable channel to
> > see how it sounds.
> >
> > Dan Marshall
>
> I don't know if these V-fets are what I am thinking about. V-fets were
> first made by Siliconix, they were the first power fets. However, like
> all standard solid state devices, they have a very high output
> impedance. Power J-fets have very different structure, and are also
> called "static-induction transistors", or SIT's. I have seen a
> reference to them in Motorola's "RF Application Reports", HB215/D,
> p 430, written in '89. More information is in "Power Transistors:
> Device Design and Applications", an IEEE Press book, p 303 thru 316.
> If any of you ever see the curves for these devices, you will see what
> I mean when I say they look EXACTLY like a triode's. Even the positive
> voltage curve looks just like a triode's positive curve. Power J-fets
> require a large negative voltage to turn off, with a mu of just 9 on
> one of the photos. Compare that to the mu of hundreds or thousands on
> all other solid state devices!
>
> Phil
=========================================================================
From: connlyra@gol.com
Subject: Re: [JN] Feedback
Date: Sat, 6 May 2000 02:29:06 +0900
Source: Sound Digest Archive v02.n540
Phil,
As with tubes, solid-state, sushi, the piano, and many other things,
feedback is just another tool - it has no way of knowing how good
your chops are.
It can only do what _you_ tell it to. Or rather, it can only sound as
good as you allow it to.
Without doubt, there are many poorly-implemented high feedback
amplifiers that sound downright lousy. But at the same time, it is
quite possible to design and build very good-sounding circuits that
use large amounts of local - and global - feedback.
>The only possible exception, which I have never seen used, is the
>"power j-fet". These remarkable devices have outputs that look
>EXACTLY like a triode's, except that the "plate" impedance is 2
>ohms! No transformer needed, and no feedback either.<
I haven't seen any JFETs specifically classified as "power JFETs",
although there have been JFETs that could handle a fair amount of
power. (I assume that you aren't interested in depletion-mode
MOSFETs.)
The 2SK63 that Jean-Michel mentioned was a Sony vertical JFET rated
at -120V (GDO), -10V (VGS), 200mA and 470mW of power. It came in
something like a TO-39 can. There was another, similar Sony V-JFET
called the 2SK79, and this could take up to 200mA and 750mW.
Depending on whether you want to make power amps or preamps, more
interesting was Sony's 2SK60 (complementary 2SJ18), a -170V V-JFET
that could pass 5A and dissipate up to 63W. The Cis was 190pF, but
that is still a lot lower than many IRF or Intersil MOSFETs.
I know that NEC had similar stuff as well.
There was the 2SK69 (comp. 2SJ19), rated at -140V, 100mA and 800mA.
For power amps, NEC offered the 2SK70 (comp 2SJ20), a -100V V-JFET
that could pass 10A and dissipate 100W.
If anyone finds any of these devices or knows of a source, do let me
know. I wouldn't mind trying them out.
For what it is worth, our upcoming Connoisseur 4.0 preamp uses a
compound-cascoded current-mode Class-A JFET output stage. Some
debugging pains at first, but now works well and sounds ok.
jcarr
ps. BTW, here is an interesting article on the application of feedback.
http://search.ieice.or.jp/1999/pdf/e82-c_5_725.pdf
Doubtless, the methods described are not at all relevant to most
people here, but nevertheless, some may find the concepts interesting.
=========================================================================
From: "Jon Lane" <jhlane@email.msn.com>
Subject: RE: [JN] Feedback
Date: Sat, 6 May 2000 08:21:28 -0600
Source: Sound Digest Archive v02.n541
> > > > Sony use to manufacture those power Vfets
> 15 years ago or so.
> > > > There was complementary P and N Vfets. I
> remember a Sony amplifier
> > > > that used those Vfets.
Just caught this thread - I vividly recall that amp, except
the model #. Big silver integrated? We had one go thru and
wired it to some sort of fairly capable bass box.
Literally, I've never heard that kind of bump and drive and
harmonic rightness in the bass from a sand amp. Made a
mental note to try and find one again some day for sub duty.
Anyone recall the model?
Jon Lane
=========================================================================
From: tube@jump.net
Subject: [JN] Feedback
Date: Sat, 06 May 2000 10:58:18 -0500
Source: Sound Digest Archive v02.n541
"Daniel J. Marshall" wrote:
> > Sony use to manufacture those power Vfets 15 years ago or so.
> > There was complementary P and N Vfets. I remember a Sony amplifier
> > that used those Vfets.
> >
> > For what it seems some low power Vfets still exist (even if not
> > still manufactured). I saw in a paper in MJ a preamplifier that
> > uses such Vfet in a SRPP stage. (If memory serves the reference
> > is something like 2SK63)
> >
> > Best regards,
> >
> > Jean-Michel Le Cleac'h
>
> Hi All,
>
> Say, I have a Yamaha B-1 basic power amp that uses V Fet outputs (2SK77s
> mfg by Yamaha, so they say in the service manual), a big bruser of an
> amp weighing some 92 lbs. It has one dead channel, quite possibly bad
> opt devices, though I have not checked it out. Does anyone happen to
> have any such devices, or know where they can be bought. It also uses
> several other V FET devices
>
> I have never seen a more complex amp, it uses 39 FETS, 113 transistors,
> 3 LEDs, 64 diodes and 7 Zeners. That ought to be enough parts to really
> screw up the sound. Perhaps I should listen to the operable channel to
> see how it sounds.
>
> Dan Marshall
I don't know if these V-fets are what I am thinking about. V-fets were
first made by Siliconix, they were the first power fets. However, like
all standard solid state devices, they have a very high output
impedance. Power J-fets have very different structure, and are also
called "static-induction transistors", or SIT's. I have seen a
reference to them in Motorola's "RF Application Reports", HB215/D,
p 430, written in '89. More information is in "Power Transistors:
Device Design and Applications", an IEEE Press book, p 303 thru 316.
If any of you ever see the curves for these devices, you will see what
I mean when I say they look EXACTLY like a triode's. Even the positive
voltage curve looks just like a triode's positive curve. Power J-fets
require a large negative voltage to turn off, with a mu of just 9 on
one of the photos. Compare that to the mu of hundreds or thousands on
all other solid state devices!
=========================================================================
From: Ken Gilbert <ride5000@ride.ri.net>
Subject: Re: [JN] Feedback
Date: Sat, 06 May 2000 11:36:44 -0400
Source: Sound Digest Archive v02.n541
>Anyway, to feedback. You are right that the "type 2" feedback should
>be called something. Maybe this is one of those cases where we get
>used to thinking about things a certain way, and nothing else makes
>sense. I have a hard time thinking of it as anything except the output
>impedance characteristic of the device in question. For one thing, a
>low output impedance can be simulated simply by placing a resistor in
>parallel with the load. Is this feedback? It is similar to feedback in
>that it "fights" to hold the load stable--but then, so does a battery.
i've always, at least in my own mind, considered this to be "degeneration,"
much like the degeneration that occurs in a common cathode stage sans bypass
cap. while it is true that the unbypassed cathode resistor provides current
feedback, it does NOT fit the critera that you outlined in NFB #1, in that it
does NOT cause the input voltage to vary when the output is wiggled.
i call anything that doesn't have a loop involved "degeneration." the low
dynamic plate impedance of a triode has no loop, and does not affect the input
node, so it's right to try to differentiate between that and the other fb
mechanism.
>In a real sense, feedback "imitates" a low output impedance.
i don't know about "imitates," though--the output impedance IS low, as long as
the NFB is operating properly.
>Matti
>Otala did a thorough analysis of feedback after a discussion among
>several people in "The Audio Critic", and apparently proved that
>negative feedback ALWAYS transforms amplitude distortions into phase
>distortions. I haven't read the paper, and wouldn't understand it if
>I did, but my instincts tell me that the "there aint no free lunch"
>conclusion of this paper is dead accurate.
the problem is that there is no such thing as a perfect nfb mechanism.
kg
=========================================================================
From: evaguido <EvaGuido@iaehv.nl>
Subject: Re: [JN] Feedback
Date: Sat, 06 May 2000 19:49:48 +0200
Source: Sound Digest Archive v02.n541
dear all,
Phil wrote a long respons and ended up with:
>But, like triodes, it would NOT need feedback to have low output
>impedance. Most of the advantage that triodes have over pentodes may
>be due to their freedom from feedback.
I want to point out that a feedback mechanism is already present inside the
triode (influence of anode votlage on the current)
Due to this, overall feedback is not realy needed anymore.
Please stay aware that triodes "have" feedback as well
Have fun
Guido
A power J-Fet amp would have
>this same advantage, which means that it might come in a close second
>to tube amps, maybe even to triode amps, for a fraction of the cost.
>
>Besides, it would be so cool ...
>
>Phil
>
>
>
>
=========================================================================
From: evaguido <EvaGuido@iaehv.nl>
Subject: Re: [JN] Feedback
Date: Sat, 06 May 2000 19:49:49 +0200
Source: Sound Digest Archive v02.n541
>I have never seen a more complex amp, it uses 39 FETS, 113 transistors,
>3 LEDs, 64 diodes and 7 Zeners. That ought to be enough parts to really
>screw up the sound. Perhaps I should listen to the operable channel to
>see how it sounds.
>
>Dan Marshall
that is: If you do not know how to apply the properly
Have fun
Guido
=========================================================================
From: evaguido <EvaGuido@iaehv.nl>
Subject: Re: [JN] Feedback
Date: Sat, 06 May 2000 19:49:51 +0200
Source: Sound Digest Archive v02.n541
Phil wrote,
>Well, I'm not sure I understand your question. A triode has low
>impedance because the plate physically attracts the electrons, and the
>grid has to "fight", so to speak, to stop them.
Yes
>I guess the real
>characteristic of a triode is that the grid does not have complete
>control over the current.
True, the anode controls the curent as well and could be considered as one
of the grids
>With a pentode or transistor, the plate or
>collector simply has no, or at least very little, control.
Yes. That is the influence of the anode is decreased due to the G2
(consiered that that voltage is kept constant with respect to the cathode)
>A power
>J-fet also has a "straight path" for the electrons to move, with gates
>on either side, just like a grid, which have to fight to close off the
>electron path. It's an inherent feature of the design.
Yes
>Anyway, to feedback. You are right that the "type 2" feedback should
>be called something. Maybe this is one of those cases where we get
>used to thinking about things a certain way, and nothing else makes
>sense. I have a hard time thinking of it as anything except the output
>impedance characteristic of the device in question.
I agree but that is only valid in the example I gave
>For one thing, a
>low output impedance can be simulated simply by placing a resistor in
>parallel with the load.
Yes
>Is this feedback?
mmmh...
>It is similar to feedback in
>that it "fights" to hold the load stable--but then, so does a battery.
>
>Feedback, to my mind, MUST contain a "return to an earlier point", the
>control voltage prior to the output. Because it returns to an earlier
>point, it contains a delay, which in turn can be used to create
>oscillation. A "real" low output impedance cannot do this.
so then we do not call that feedback but "terugwerking"
>In a real sense, feedback "imitates" a low output impedance. Matti
>Otala did a thorough analysis of feedback after a discussion among
>several people in "The Audio Critic", and apparently proved that
>negative feedback ALWAYS transforms amplitude distortions into phase
>distortions. I haven't read the paper, and wouldn't understand it if
>I did, but my instincts tell me that the "there aint no free lunch"
>conclusion of this paper is dead accurate. If you are careful, I
>think that a fair amount of feedback can be tolerated, at least up
>to the point where the ear starts noticing the increased phase
>distortion, but I suspect that that's it. Triodes don't need any,
>any they sound better than anything else. I am willing to bet good
>money that no feedback is the big reason why. Of course, I tend to
>lose good money, so ... (I am also going to respectfully disagree
>with jcarr on this one, although I am sure he also knows way more
>about electronics than I do).
>
>As long as we understand the differences between the two mechanisms,
>I suspect that we can call them almost anything and it won't matter.
>To simply declare that it "is output impedance", now that I think
>about it, is stupid. That is how I look at it, but it has several
>effects, and it is the effects that matter, not the name. If type 2
>feedback brings to mind those effects, then that is what you should
>call it.
In general I agree, the reason I brought it up here was only to make it
clear that vaious mechanisms are present...........
Guido
>Phil
>
>
>
>
=========================================================================
From: "PEARL Cust Serv" <custserv@pearl-hifi.com>
Subject: Re: [JN] Feedback
Date: Sun, 07 May 2000 15:08:43 -0600
Source: Sound Digest Archive v02.n541
Hi All:
I've been off-list for a while so I'm not completely sure that my post
will turn out to be relevant.
As this discussion seems to be about what I loosely call the "plate
degeneration" that is almost central to the low gain, low distortion and
lowish output impedance that are characteristic of triode operation, the
following link to a PDF version of an article I reformatted for inclusion in
the Audio Notes will likely be helpful.
http://homepage.mac.com/planet10/PEARL-hifi/papers.html
Originally published by Stockman in the late 50s, the premise is that a
triode can be successfully modeled as an infinite-impedance pentode around
which feedback has been applied, albiet with no time delay related
artifacts.
While I normally snip most of the text to which I make comments, I've
left this post untouched so that you can refer back and forth between
Stockman's, "Inherent Feedback in Triodes" and this discussion . . . .
Best regards,
Bill - PEARL, Inc.
I can hardly wait for the dinosaurs to die off . . . . again !
=================================================================
Evaguido wrote:
> Phil wrote,
>>Well, I'm not sure I understand your question. A triode has low
>>impedance because the plate physically attracts the electrons, and the
>>grid has to "fight", so to speak, to stop them.
>
> Yes
>
>>I guess the real
>>characteristic of a triode is that the grid does not have complete
>>control over the current.
>
> True, the anode controls the curent as well and could be considered as one
> of the grids
>
>>With a pentode or transistor, the plate or
>>collector simply has no, or at least very little, control.
>
> Yes. That is the influence of the anode is decreased due to the G2
> (consiered that that voltage is kept constant with respect to the cathode)
>
>>A power
>>J-fet also has a "straight path" for the electrons to move, with gates
>>on either side, just like a grid, which have to fight to close off the
>>electron path. It's an inherent feature of the design.
>
> Yes
>
>>Anyway, to feedback. You are right that the "type 2" feedback should
>>be called something. Maybe this is one of those cases where we get
>>used to thinking about things a certain way, and nothing else makes
>>sense. I have a hard time thinking of it as anything except the output
>>impedance characteristic of the device in question.
>
> I agree but that is only valid in the example I gave
>
>>For one thing, a
>>low output impedance can be simulated simply by placing a resistor in
>>parallel with the load.
>
> Yes
>
>>Is this feedback?
>
> mmmh...
>
>>It is similar to feedback in
>>that it "fights" to hold the load stable--but then, so does a battery.
>>Feedback, to my mind, MUST contain a "return to an earlier point", the
>>control voltage prior to the output. Because it returns to an earlier
>>point, it contains a delay, which in turn can be used to create
>>oscillation. A "real" low output impedance cannot do this.
>
> so then we do not call that feedback but "terugwerking"
>
>>In a real sense, feedback "imitates" a low output impedance. Matti
>>Otala did a thorough analysis of feedback after a discussion among
>>several people in "The Audio Critic", and apparently proved that
>>negative feedback ALWAYS transforms amplitude distortions into phase
>>distortions. I haven't read the paper, and wouldn't understand it if
>>I did, but my instincts tell me that the "there aint no free lunch"
>>conclusion of this paper is dead accurate. If you are careful, I
>>think that a fair amount of feedback can be tolerated, at least up
>>to the point where the ear starts noticing the increased phase
>>distortion, but I suspect that that's it. Triodes don't need any,
>>any they sound better than anything else. I am willing to bet good
>>money that no feedback is the big reason why. Of course, I tend to
>>lose good money, so ... (I am also going to respectfully disagree
>>with jcarr on this one, although I am sure he also knows way more
>>about electronics than I do).
>>
>>As long as we understand the differences between the two mechanisms,
>>I suspect that we can call them almost anything and it won't matter.
>>To simply declare that it "is output impedance", now that I think
>>about it, is stupid. That is how I look at it, but it has several
>>effects, and it is the effects that matter, not the name. If type 2
>>feedback brings to mind those effects, then that is what you should
>>call it.
>
> In general I agree, the reason I brought it up here was only to make it
> clear that various mechanisms are present...........
>
> Guido
>
>
>>Phil
=========================================================================
From: Ken Gilbert <ride5000@ride.ri.net>
Subject: Re: [JN] Feedback
Date: Sun, 07 May 2000 18:26:07 -0400
Source: Sound Digest Archive v02.n541
> http://homepage.mac.com/planet10/PEARL-hifi/papers.html
bill, excellent link and post. thank you for your good timing...
ken
=========================================================================
From: connlyra@gol.com
Subject: [JN] Feedback article
Date: Fri, 5 May 2000 04:20:55 +0900
Source: Sound Digest Archive v02.n539
I encountered an interesting article on the application of feedback.
The link is http://search.ieice.or.jp/1999/pdf/e82-c_5_725.pdf
Doubtless, the methods described are not at all relevant to most
people here, but nevertheless, some may find the concepts interesting.
jcarr
=========================================================================
From: Grover Gardner <groverg@postoffice.att.net>
Subject: [JN] Feedback as attenuator?
Date: Tue, 7 Sep 1999 22:38:30 -0400
Source: Sound Digest Archive v02.n273
I'm going to be reading up on feedback this week, to understand it better
(read: at all :-)). I'm particularly interested in using some form of
feedback as a volume control in a preamp, and wondered if anyone has any
experience and/or thoughts on this. I'm thinking of a medium-gain tube
driving a beefy low-mu tube for low-impedance/high-current output, with
some sort of feedback between the two to attenuate the signal. Series
feedback? Parallel? Any thoughts?
Grover Gardner
groverg@postoffice.att.net
=========================================================================
From: SBench@aol.com
Subject: Re: [JN] Feedback as attenuator?
Date: Wed, 8 Sep 1999 00:55:24 EDT
Source: Sound Digest Archive v02.n273
In a message dated 99-09-08 00:16:19 EDT, groverg@postoffice.att.net writes:
<<
I'm going to be reading up on feedback this week, to understand it better
(read: at all :-)). I'm particularly interested in using some form of
feedback as a volume control in a preamp, and wondered if anyone has any
experience and/or thoughts on this. I'm thinking of a medium-gain tube
driving a beefy low-mu tube for low-impedance/high-current output, with
some sort of feedback between the two to attenuate the signal. Series
feedback? Parallel? Any thoughts?
Grover Gardner >>
Hi Grover,
If the plate voltage of the 2 tubes is anywhere near close you could
do something like this: (fixed font ASCII graphics crap)
| |
| |
/ /
/RP1 / RP2
/ /
| |
| Vol |
+---------////--------+-----out
| ^ |
| | |
| | |
--- = cap |
- - - | ----
___ |
| +------- - - -
| ___
/ |
/ Rg |
/
|
|
gnd or bias
With the pot towards the left gain is maximum, feedback is minimum,
with the pot to right, gain is minimum, feedback is maximum. Since
it's local feedback over one stage there is not much sonic penalty
(IMHO).
Try it. You might like it.
Best Regards,
Steve
=========================================================================
From: "Fred Volz" <fcv@emotiveaudio.com>
Subject: Re: [JN] Feedback as attenuator?
Date: Wed, 8 Sep 1999 01:12:29 -0400
Source: Sound Digest Archive v02.n273
Grover asked:
>Grover Gardner
>groverg@postoffice.att.net
I'm particularly interested in using some form of
>feedback as a volume control in a preamp, and wondered if anyone has any
>experience and/or thoughts on this.
Just off the top of my head, I think this will sound really bad. My
experience has been that even small amounts of feedback really compromise
the sound of line stages (power amplifiers seem a bit less affected by
feedback). For example, in adding feedback to try to use higher mu tubes
than would otherwise be practical for a line stage I have found the damage
done more than erases any desirable qualities these tubes might have had to
begin with. However, my experience with this has been limited to my own
preamp (your experience may be different). I would think--and this may be
completely wrong--that the harm done to the sound by a good volume control
is less than the harm done by adding feedback, especially in varying
amounts.
Best wishes
Fred Volz
fcv@emotiveaudio.com
=========================================================================
From: "Le Cleac'h J.-M." <lecleach@cgi.ensmp.fr>
Subject: Re: [JN] Feedback as attenuator?
Date: Wed, 8 Sep 1999 09:40:07 +0200
Source: Sound Digest Archive v02.n273
- ----------
> De : Grover Gardner <groverg@postoffice.att.net>
> A : sound@deliverator.io.com
> Objet : [JN] Feedback as attenuator?
> Date : mercredi 8 septembre 1999 04:38
>
> I'm going to be reading up on feedback this week, to understand it better
> (read: at all :-)). I'm particularly interested in using some form of
> feedback as a volume control in a preamp, and wondered if anyone has any
> experience and/or thoughts on this. I'm thinking of a medium-gain tube
> driving a beefy low-mu tube for low-impedance/high-current output, with
> some sort of feedback between the two to attenuate the signal. Series
> feedback? Parallel? Any thoughts?
> Grover Gardner
> groverg@postoffice.att.net
Hello,
Strangely, it happened that I build recently a preamp using such "local
feedback" gain control.
Between the 2Volts output of my CD player and the input of the FDS388
digital crossover I needed a low gain preamplifier. (not needed with my
RIAA preamp which one can delivers signals more than 10V RMS)
As mean recording volume varies a lot from CD to CD, I wanted to have a
gain control but didn't want to have a potentiometer after the transformer
output of my CD player nor at the input of the FDS388 (because I need the
volume control near of me and the FDS being in my bedroom I have 10 x 8
meters audio cables and I don't want a potentiometer in front of 8 meters
of audio cables...)
I designed a very simple preamplifier based on an EF86 pentod screen
driven, grid is grounded and the gain is controlled by a variable resistor
(for the moment a potentiometer with one lead and the cursor wired
together):
For what it worths,I give you the ASCII schematics of that preamplifier:
o------o-------------o------B+
| | |
R1 R2 |
| | drain
| o-----------gate BUZ80A
| EF86 | source
| plate |
| supressor--o |
INPUT --C1-o----screen | o--C2--OUTPUT
o----grid | |
| cathod | |
| | | |
| o--------o R3 / or a \
| | | | current |
| o-->P1 | \ source /
| | | |
o--o---o-------------o-------GROUND
The distortion spectrum is only H2.
It is a prototype and I am still working on that preamp but I used to
listen to it since several month and I think it is not bad.
(several friends from the Joenet who visited me here in Paris in the same
period didn't find it too bad too...)
Best regards,
Jean-Michel Le Cleac'h, Paris, France
=========================================================================
From: Allen Wright <AllenVSE@compuserve.com>
Subject: [JN] Feedback as attenuator?
Date: Wed, 8 Sep 1999 08:50:30 -0400
Source: Sound Digest Archive v02.n274
Grover asked:
>>> I'm thinking of a medium-gain tube
driving a beefy low-mu tube for low-impedance/high-current output, with
some sort of feedback between the two to attenuate the signal. Series
feedback? Parallel? Any thoughts?<<<
My thought is: Why?
Any type of loop NFB (series, parallel, whatever) as you are suggesting
kills the sonics in my experience - and I've tried it all ways I know of.
Attenuate the signal with the thing for the job - an attenuator - or set
the circuit up with less gain to start with...
Regards, Allen (VSE)
=========================================================================
From: tube@jump.net
Subject: [JN] Feedback as attenuator?
Date: Thu, 09 Sep 1999 14:10:50 -0500
Source: Sound Digest Archive v02.n274
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Grover,
If I understand you correctly, you want to explore the use of feedback as a
way to *eliminate* the need for a high quality, very expensive potentiometer.
My first thought was the rock-band bass-player's response to Mr. Rogers
(in the Edie Murphy skit), when Mr. Rodgers said, "What time do you get up,
Mr. bass player? I get up at 6 AM." After choking a bit, the bass-player
said,
"That's insane! You're stupid ..."
Truthfully, from what I have read and heard (haven't actually *made* anything
yet, I confess), that is a crazy idea, as the sonic harm from feedback will
be
greater than the harm from an inexpensive pot. Unless of course, you use a
circuit like Steve's--which needs a very high quality pot to work best (I
think),
which leaves you back at square one.
There is another possibility, which I have thought about for years, but never
tried or seen tried, namely beam-deflection tubes. These tube have a pair of
deflection plates, like a CRT, which directs the electron flow to two
side-by-
side plates (anodes). As the voltage on the deflection plates is varied--say
the
left deflection plate becomes more and more positive and the right more and
more negative--an increasing percentage of the current starts going to the
left
anode. The output would simply be taken from one of the plates, which get
from 0 to 100% of the current, making this a "tube-potentiometer", with an
el-cheapo pot controlling the deflection plates!
There are problems, of course. Since a current division exists (similar to a
screen grid), there will be a slight increase in noise. Also, the division of
current probably does not remain constant at all current levels, although
this
should merely produce a (hopefully mild) 2nd order distortion. Also, if the
tube is driven from the grid, then the sound will be limited by the quality
of
these tubes, which may or may not be great. This could be taken care of, if
necessary, by using them in a cascode configuration. A great tube supplies
the current, while the beam-deflection tube merely passes this current to the
two plates. In the simple current-in equals current-out process inherent to
the grounded grid-configuration, this should do very little harm--we hope.
Finally, with a normal resistor to power supply output, the DC output voltage
will vary wildly due to the massive change in DC current. This one is hard to
get around. My best thought on this is to use a current source load which
transforms into a voltage source at very low frequencies. This is not as bad
as it sounds.
|
|
-----
-----
-----
----\/\/\/\/---------- -----
| | -----
| | |
----- ===== |
--- | |
----- | |
--- ---------|
| |
Uh, that's *supposed* to be a battery on the left, and a pentode on the
right (how do you guys do that?). Anyway, at high frequencies, it is a
current source, but at low frequencies, the cathode voltage remains
relatively constant, which is what we need. To really work this needs a
floating power supply for the screen. You can get around that too, but
that's enough on this subject for now!
Look forward to hearing thoughts about and/or experiences with
something like this.
Phil
Grover Gardner wrote:
> I'm going to be reading up on feedback this week, to understand it better
> (read: at all :-)). I'm particularly interested in using some form of
> feedback as a volume control in a preamp, and wondered if anyone has any
> experience and/or thoughts on this. I'm thinking of a medium-gain tube
> driving a beefy low-mu tube for low-impedance/high-current output, with
> some sort of feedback between the two to attenuate the signal. Series
> feedback? Parallel? Any thoughts?
> Grover Gardner
> groverg@postoffice.att.net
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<!doctype html public "-//w3c//dtd html 4.0 transitional//en">
<html>
Grover,
<p>If I understand you correctly, you want to explore the use of feedback
as a
<br>way to *eliminate* the need for a high quality, very expensive potentiometer.
<br>My first thought was the rock-band bass-player's response to Mr. Rogers
<br>(in the Edie Murphy skit), when Mr. Rodgers said, "What time do you
get up,
<br>Mr. bass player? I get up at 6 AM." After choking a bit, the bass-player
said,
<br>"That's insane! You're stupid ..."
<p>Truthfully, from what I have read and heard (haven't actually *made*
anything
<br>yet, I confess), that is a crazy idea, as the sonic harm from feedback
will be
<br>greater than the harm from an inexpensive pot. Unless of course, you
use a
<br>circuit like Steve's--which needs a very high quality pot to work best
(I think),
<br>which leaves you back at square one.
<p>There is another possibility, which I have thought about for years,
but never
<br>tried or seen tried, namely beam-deflection tubes. These tube have
a pair of
<br>deflection plates, like a CRT, which directs the electron flow to two
side-by-
<br>side plates (anodes). As the voltage on the deflection plates is varied--say
the
<br>left deflection plate becomes more and more positive and the right
more and
<br>more negative--an increasing percentage of the current starts going
to the left
<br>anode. The output would simply be taken from one of the plates, which
get
<br>from 0 to 100% of the current, making this a "tube-potentiometer",
with an
<br>el-cheapo pot controlling the deflection plates!
<p>There are problems, of course. Since a current division exists (similar
to a
<br>screen grid), there will be a slight increase in noise. Also, the division
of
<br>current probably does not remain constant at all current levels, although
this
<br>should merely produce a (hopefully mild) 2nd order distortion. Also,
if the
<br>tube is driven from the grid, then the sound will be limited by the
quality of
<br>these tubes, which may or may not be great. This could be taken care
of, if
<br>necessary, by using them in a cascode configuration. A great tube supplies
<br>the current, while the beam-deflection tube merely passes this current
to the
<br>two plates. In the simple current-in equals current-out process inherent
to
<br>the grounded grid-configuration, this should do very little harm--we
hope.
<br>Finally, with a normal resistor to power supply output, the DC output
voltage
<br>will vary wildly due to the massive change in DC current. This one
is hard to
<br>get around. My best thought on this is to use a current source load
which
<br>transforms into a voltage source at very low frequencies. This is not
as bad
<br>as it sounds.
<p><tt> &nb
sp;
|</tt>
<br><tt> &n
bsp;
|</tt>
<br><tt> &n
bsp;
- -----</tt>
<br><tt> &n
bsp;
- -----</tt>
<br><tt> &n
bsp;
- -----</tt>
<br><tt> ----\/\/\/\/---------- -----</tt>
<br><tt> |
| -----</tt>
<br><tt> |
| |</tt>
<br><tt> -----
===== |</tt>
<br><tt> ---
| |</tt>
<br><tt> -----
| |</tt>
<br><tt> ---
- ---------|</tt>
<br><tt> |
|</tt><tt></tt>
<p>Uh, that's *supposed* to be a battery on the left, and a pentode on
the
<br>right (how do you guys do that?). Anyway, at high frequencies, it is
a
<br>current source, but at low frequencies, the cathode voltage remains
<br>relatively constant, which is what we need. To really work this needs
a
<br>floating power supply for the screen. You can get around that too,
but
<br>that's enough on this subject for now!
<p>Look forward to hearing thoughts about and/or experiences with
<br>something like this.
<p>Phil
<p>Grover Gardner wrote:
<blockquote TYPE=CITE>I'm going to be reading up on feedback this week,
to understand it better
<br>(read: at all :-)). I'm particularly interested in using some
form of
<br>feedback as a volume control in a preamp, and wondered if anyone has
any
<br>experience and/or thoughts on this. I'm thinking of a medium-gain
tube
<br>driving a beefy low-mu tube for low-impedance/high-current output,
with
<br>some sort of feedback between the two to attenuate the signal.
Series
<br>feedback? Parallel? Any thoughts?
<br>Grover Gardner
<br>groverg@postoffice.att.net</blockquote>
</html>
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=========================================================================
From: tube@jump.net
Subject: [JN] Feedback as attenuator?
Date: Fri, 10 Sep 1999 00:53:19 -0500
Source: Sound Digest Archive v02.n275
Oops! Forgot to include the numbers of beam deflection tubes. The ones I
know of are 6AR8, 6HW8, 6JH8, 6ME8, and 7360. Detailed plate curves
for the 6ME8 are in RCA's receiving tube manual RC-30, and probably some
earlier editions (but not back to RC-23). Curves for the 7360 are in
RCA's
transmitting tubes manual TT-5. The tube schematics cab be a bit
confusing;
for everything except the 7360 it looks like there is an "extra" grid in
the path
of the electrons. In reality, however, there is nothing in the electron
path, and
this "grid" actually refers to extra shielding inside the tube,
something which the
7360 does not have. In any case, all of these tubes can require an
external
tube shield, depending on the surrounding electromagnetic conditions.
The
7360 is the only expensive one of the lot. If the usual Rules of Life
apply, this
means that it sounds better ...
Phil
=========================================================================
From: Tom Ronan <tronan@enteract.com>
Subject: [JN] feedback based volume control
Date: Mon, 01 May 2000 23:27:33 -0500
Source: Sound Digest Archive v02.n537
I have a few questions about a subject that has been in my mind for some
time. The recent volume control, low impedance thread renewed the idea in
my mind.
One of the major problems I find with volume controls is not the inherently
evil resistance, but the input capacitance of tubes. A series resistor and
a cap to ground is a filter which attenuates high frequencies. We put a
little resistor in and call it a grid stopper - basically a device to roll
of high (too high) frequencies that cause trouble in our audio devices.
Like Dave, though, I've found that a lower volume control gives better
sound. I've never gotten down to 600 ohms, but at 10k things are a nice
improvement. With a 500K volume control, almost all of the time you have a
big resistor in series with your grids. 400K or more! Even a 50K resistor
leaves more than half of it's value in series almost all of the time.
However, however good sounding a 10k pot is, it requires a big cap in the
preceding stage (2 mics or more) and they're not so good sounding
usually. Other than transformer coupling everything at 600 ohms (which is
great until you need to listen to a non custom built component, or you want
to change something and you only have one nice pair of trannys for inputs,
etc.) I had an idea about using feedback for a volume control.
Some time ago, Grover and I discussed this, and he tried it out with not so
great results. I'm pretty sure it can be implemented. Here are the broad
sketches of my idea, and my setup process. Please provide any corrections
you feel like or any other ways to accomplish this volume control.
In the schematic below, a cap, pot and resistor are connected from the
plate of a tube to the input of the tube.
B+
|
o
|
|
|
R (plate resistor)
Feedback Cap |
o-)(-----|
| |
Rf |
| o output coupling cap o---------o
(pot) |
| Plate
INPUT o------Grid
| Cathode
| |
Rg Rk + Ck
| |
o--------o
|
GROUND
The capacitor blocks the dc on the plate and allows only ac signal to pass
(just like an output coupling cap). The pot and the Rf (for feedback) form
a voltage divider with the grid resistor.
A simple rc coupled amp reverses phase so that the ac signal output on the
plate is out of phase with the ac signal on the input. When combined, the
out of phase signal "subtracts" from the input signal.
The first problem is that for a tube with a net gain of (say) 6, the output
signal is 6 times larger than the input signal. So if you subtract the
complete output signal from the input signal you'll get (1 - 6 = -5) 5
times the signal out of phase sent into the input. However, if you divide
the output by 1/(net gain) then you'll get a feedback signal equal to the
input signal.
This could be accomplished (most easily) by placing a pot in the grid
circuit and dialing it in until there was no volume from the amplification
stage. The value of resistors would be based on this relationship:
Rg
net gain * ------- = 1
pot+Rg
(The second half is the same formula as for a voltage divider such as a
typical input pot.)
At this point, the volume would be zero - the input perfectly cancelling
the output. The value of the pot could then be replaced by a fixed
resistor and would then be considered Rf in the schematic above.
Any value greater than this would tend to increase the volume since the
value of the output signal (after dividing down from the Rf) would be
smaller than the input signal. Voila, turn the pot, increase the volume! A
feedback volume control.
Practically speaking for a 26 line stage, Rf must be about 6 times Rg. If
you have an Rg of around 50k, Rf must be around 300K. For a loud volume
the feedback pot would have to be on the order of 2 megs or more. The
feedback cap size must be set to the same size as if you were coupling from
the output of this stage to an Rg of the same size. In this example, the
value of .5 would be fine.
- ---------------------------
Ok -- so what's wrong with this idea? It takes the series resistor out of
the direct connection from the input to the grid, but replaces it with
another resistor in the feedback path (still in series to the grid). Is
this just the same thing? A pointless over-complication, or something to
make quiet volumes sound better and get the better highs of a lower
resistance volume control?
Would it be better to use a pentode with a variable screen voltage as a
volume control? (I'm not afraid of pentodes - at least if they're direct
heated. A 33 would make a nice line stage in this screen-based volume
control application.)
Has anyone tried something like this? Does it work? Does it sound any
good? Thanks for any input.
Tom
- ---------------------------------------------------------
Tom Ronan 1045 W. Montana Chicago, IL 60614
Lowther America http://www.lowther-america.com
26 Preamp & Hedlund Horns http://www.enteract.com/~tronan
=========================================================================
From: "Cameron E." <ce001@hotmail.com>
Subject: Re: [JN] feedback based volume control
Date: Tue, 02 May 2000 07:26:02 GMT
Source: Sound Digest Archive v02.n537
It's funny you bring this up; I was thinking the very _same_ thing last
night, at least about the pentodes. I'm stuck in Stockholm, Sweden, for a
year, without any of my audio stuff, so I can't try this and put my butt
where my mouth is. It's on my list of circuits to build when I return to
Seattle, however.
Check out the Raditron Designer's Handbook, 4th edition, in the area on
automatic volume control circuits for radios. Their pentode idea is such
that you use a pentode as a shunt element to ground, which, to me, seems
like removing the tube itself entirely from the audio path. The signal
itself is input coupled, via a cap, to the plate of the pentode, and the
output is again cap coupled directly from there. There's some feedback and
the grid bias of said pentode is then adjusted to bring the tube closer to
or further from cutoff, changing the amount of "shunting" to ground.
It would seem to me that you could place a pot in the grid line of the
pentode and therefore use any old cheap pot - junk box or Radio Shack, even,
since it's totally out of the circuit. Using this pot, the bias could then
be adjusted. The original circuit in the handbook intended for the bias to
be supplied from an external circuit, automatically, but I don't see any
reason why a voltage divider and a bias source couldn't be used.
As to the sonic penalties of doing this, I don't know...you pay for it in
complexity - the extra tube, in power consumption - again the tube, and
sonically, at the _very least_ with two more capacitors in the audio line.
The questions I have are more in regards to the loading - what does this do
for the previous and next stages as far as load and source impedance are
concerned? Anyone care to comment on the sonics?
>From: Tom Ronan <tronan@enteract.com>
>To: sound@lists.io.com
>Subject: [JN] feedback based volume control
>Date: Mon, 01 May 2000 23:27:33 -0500
>
>I have a few questions about a subject that has been in my mind for some
>time. The recent volume control, low impedance thread renewed the idea in
>my mind.
>
>One of the major problems I find with volume controls is not the inherently
>evil resistance, but the input capacitance of tubes. A series resistor and
>a cap to ground is a filter which attenuates high frequencies. We put a
>little resistor in and call it a grid stopper - basically a device to roll
>of high (too high) frequencies that cause trouble in our audio devices.
>
>Like Dave, though, I've found that a lower volume control gives better
>sound. I've never gotten down to 600 ohms, but at 10k things are a nice
>improvement. With a 500K volume control, almost all of the time you have a
>big resistor in series with your grids. 400K or more! Even a 50K resistor
>leaves more than half of it's value in series almost all of the time.
>
>However, however good sounding a 10k pot is, it requires a big cap in the
>preceding stage (2 mics or more) and they're not so good sounding
>usually. Other than transformer coupling everything at 600 ohms (which is
>great until you need to listen to a non custom built component, or you want
>to change something and you only have one nice pair of trannys for inputs,
>etc.) I had an idea about using feedback for a volume control.
>
>Some time ago, Grover and I discussed this, and he tried it out with not so
>great results. I'm pretty sure it can be implemented. Here are the broad
>sketches of my idea, and my setup process. Please provide any corrections
>you feel like or any other ways to accomplish this volume control.
>
>In the schematic below, a cap, pot and resistor are connected from the
>plate of a tube to the input of the tube.
>
> B+
> |
> o
> |
> |
> |
> R (plate resistor)
> Feedback Cap |
> o-)(-----|
> | |
> Rf |
> | o output coupling cap o---------o
> (pot) |
> | Plate
> INPUT o------Grid
> | Cathode
> | |
> Rg Rk + Ck
> | |
> o--------o
> |
> GROUND
>
>The capacitor blocks the dc on the plate and allows only ac signal to pass
>(just like an output coupling cap). The pot and the Rf (for feedback) form
>a voltage divider with the grid resistor.
>
>A simple rc coupled amp reverses phase so that the ac signal output on the
>plate is out of phase with the ac signal on the input. When combined, the
>out of phase signal "subtracts" from the input signal.
>
>The first problem is that for a tube with a net gain of (say) 6, the output
>signal is 6 times larger than the input signal. So if you subtract the
>complete output signal from the input signal you'll get (1 - 6 = -5) 5
>times the signal out of phase sent into the input. However, if you divide
>the output by 1/(net gain) then you'll get a feedback signal equal to the
>input signal.
>
>This could be accomplished (most easily) by placing a pot in the grid
>circuit and dialing it in until there was no volume from the amplification
>stage. The value of resistors would be based on this relationship:
>
> Rg
>net gain * ------- = 1
> pot+Rg
>
>(The second half is the same formula as for a voltage divider such as a
>typical input pot.)
>
>At this point, the volume would be zero - the input perfectly cancelling
>the output. The value of the pot could then be replaced by a fixed
>resistor and would then be considered Rf in the schematic above.
>
>Any value greater than this would tend to increase the volume since the
>value of the output signal (after dividing down from the Rf) would be
>smaller than the input signal. Voila, turn the pot, increase the volume! A
>feedback volume control.
>
>Practically speaking for a 26 line stage, Rf must be about 6 times Rg. If
>you have an Rg of around 50k, Rf must be around 300K. For a loud volume
>the feedback pot would have to be on the order of 2 megs or more. The
>feedback cap size must be set to the same size as if you were coupling from
>the output of this stage to an Rg of the same size. In this example, the
>value of .5 would be fine.
>
>---------------------------
>
>Ok -- so what's wrong with this idea? It takes the series resistor out of
>the direct connection from the input to the grid, but replaces it with
>another resistor in the feedback path (still in series to the grid). Is
>this just the same thing? A pointless over-complication, or something to
>make quiet volumes sound better and get the better highs of a lower
>resistance volume control?
>
>Would it be better to use a pentode with a variable screen voltage as a
>volume control? (I'm not afraid of pentodes - at least if they're direct
>heated. A 33 would make a nice line stage in this screen-based volume
>control application.)
>
>Has anyone tried something like this? Does it work? Does it sound any
>good? Thanks for any input.
>
>
>Tom
>
>---------------------------------------------------------
>Tom Ronan 1045 W. Montana Chicago, IL 60614
>Lowther America http://www.lowther-america.com
>26 Preamp & Hedlund Horns http://www.enteract.com/~tronan
________________________________________________________________________
Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com
=========================================================================
From: dslagle@earthlink.net (dave slagle)
Subject: Re: [JN] feedback based volume control
Date: Tue, 2 May 2000 09:24:01 -0400
Source: Sound Digest Archive v02.n537
tom and other feedback vc mavens
also in rdh there is a diagram for electronic attenuator that is
essentially a pentode used as a cathode follower with various cathode
resistors for coarse adjustment, and then the screen is used for fine
adjustment.
the only problem i see with the system as tom proposed is in the small
range of attenuation... assuming a 26, and getting the full gain of 6 thats
still only 15db of range from 0 to 100% feedback.... i guess you could go
above the 100% to further attenuate... but given the gain structure of the
12:00 club... thats a lot of feedback to get their 40db of attenuation....
while keeping along these lines...
I am wondering how little range of attenuation one can get away with... for
the most part with my current gain structure... 20 well placed db is plenty
for me... but getting that zeroed in...means the gain structure has to be
dead on... 40 db is more realistic and 50 is my goal....
this gives me the range from rocking to talking on the phone.... for the
most part 3 db steps are fine for me... i may even cheat the first 2 and
last 2 to 4db so i can go a bit finer in the middle...
i have also been wondering if trying to get 40 db in one spot isn't asking
too much?
40 db is a 100:1
60 db is a 1000:1
we already have tapped output transformers... why not put them to work and
let them start sur you will only get a few db of attenuation, but look at
how much nicer the reflected load will look to the output tube....
there was some talk a while back about series parallel combos of
secondaries for limited ranges of attenuation... why not start by working
this into our OT's
in this situation, when you increase the turns ratio... see no penalty...
or at least i think the penalty may be far better than the other options.
dave
=========================================================================
From: Grover Gardner <groverg@postoffice.att.net>
Subject: Re: [JN] feedback based volume control
Date: Tue, 2 May 2000 12:22:07 -0400
Source: Sound Digest Archive v02.n537
The preamp my friend Bruce Wenger built for me uses a feedback
network for volume control. It's a two stage design, using a
high-mu, high-trans pentode in triode configuration followed by a
low-mu power pentode, also in triode mode. Being a commercial
product of his I won't go into details and don't really know them
anyway, but the feedback loop appears to be applied to the first
stage with a 10-turn pot for control. The range of gain is limited,
and for this reason there is a gain switch which inserts or removes a
second resistance somewhere in the circuit. There is no "zero"
signal setting, of course, so a mute switch is also present, but I
find that I can listen from background levels to concert-hall volume
with no trouble. The overall gain can also be adjusted to match the
amp. It's a very clever and excellent-sounding design which Bruce
worked on for several years. So it can work and sound very good if
properly set up. I played with the idea myself, realized it was way
over my head, and just gave in and bought the preamp. :-)
- -------
Grover Gardner
groverg@postoffice.att.net
=========================================================================
From: "Darryl Lock" <dklock@ieee.org>
Subject: RE: [JN] feedback based volume control
Date: Tue, 2 May 2000 17:54:34 +1000
Source: Sound Digest Archive v02.n537
>
> The questions I have are more in regards to the loading - what
> does this do
> for the previous and next stages as far as load and source impedance are
> concerned? Anyone care to comment on the sonics?
>
Well, the diehard audio fanatics go to great trouble to remove muting
transistors from SS equipment to improve the sound. This pentode is just a
variable version of that isn't it?
Dazz
=========================================================================
From: evaguido <EvaGuido@iaehv.nl>
Subject: RE: [JN] feedback based volume control
Date: Tue, 02 May 2000 18:06:27 +0200
Source: Sound Digest Archive v02.n537
At 17:54 02/05/2000 +1000, Darryl Lock wrote:
>
>>
>> The questions I have are more in regards to the loading - what
>> does this do
>> for the previous and next stages as far as load and source impedance are
>> concerned? Anyone care to comment on the sonics?
>
>Well, the diehard audio fanatics go to great trouble to remove muting
>transistors from SS equipment to improve the sound. This pentode is just a
>variable version of that isn't it?
As I did not catch the history behind this mail, could someone eleborate on
the last remark ?
regards
Guido
>
>Dazz
>
>
>
=========================================================================
From: "Le Cleac'h J.-M." <lecleach@cgi.ensmp.fr>
Subject: Re: [JN] feedback based volume control
Date: Wed, 3 May 2000 09:32:39 +0200
Source: Sound Digest Archive v02.n538
Hello,
Here is a schematics of a preamplifier/volume control stage I used to have
during 1 year in my system (before I change for a passive preamp + stepped
attenuator).
ASCII schematics (please set your screen in COURRIER font)
B+
|
o-----o
| |
R1 R2
| |
| o----output
| |
| Plate EF86
Input o--C1--o---screen
grid-----o
cathod |
| |
VR1 |
| |
o------o
|
Ground
Vr1 is a variable resistor that controls the gain of the stage via local
feedback.
The pentode as you can see is feeded by its screen.
The stage is very linear and only H2 is present in the distortion spectrum.
Best regards,
Jean-Michel Le Cleac'h, Paris, France
=========================================================================
From: evaguido <EvaGuido@iaehv.nl>
Subject: Re: [JN] feedback based volume control
Date: Wed, 03 May 2000 19:20:21 +0200
Source: Sound Digest Archive v02.n538
dear all
I think J-M's implementation is one of the better ones as lots of other
feedback mechanisms destroy the sound.
The cathode degeneration principle is fundamentally different from the
feedback loop.
In Dutch I use different definitions
1-tegenkoppeling (traditional feedback)
2-terugwerking (I do not know any decent translation, sorry)
Have fun
Guido
At 09:32 03/05/2000 +0200, Le Cleac'h J.-M. wrote:
>Hello,
>
>Here is a schematics of a preamplifier/volume control stage I used to have
>during 1 year in my system (before I change for a passive preamp + stepped
>attenuator).
>
>ASCII schematics (please set your screen in COURRIER font)
>
> B+
> |
> o-----o
> | |
> R1 R2
> | |
> | o----output
> | |
> | Plate EF86
>Input o--C1--o---screen
> grid-----o
> cathod |
> | |
> VR1 |
> | |
> o------o
> |
> Ground
>
>Vr1 is a variable resistor that controls the gain of the stage via local
>feedback.
>
>The pentode as you can see is feeded by its screen.
>The stage is very linear and only H2 is present in the distortion spectrum.
>
>Best regards,
>
>Jean-Michel Le Cleac'h, Paris, France
>
>
>
>
=========================================================================
From: "Thomas Sylvester" <TRS@carlsmith.com>
Subject: [JN] Feedback in Pentode SE Amps
Date: Fri, 24 Mar 2000 07:11:24 -1000
Source: Sound Digest Archive v02.n494
>>> "Darryl Lock" <dklock@ieee.org> 03/23/00 06:08PM >>>
I haven't seen your circuit, but I prefer SE amps without any negative feedback.<<<
Darryl-
Very interesting and encouraging. Virtually every SE pentode amp I've seen (including J C Morrison'
s "Blackie Box" in SP 14 and Gordon Rankin's original 807 amp, as well as a number of designs on the
web that 'listers have pointed me to) uses global NFB to lower output impedance/increase damping fa
ctor to something like that seen in triode SE amps. I had assumed that this was a necessary evil of
pentode amp designs, but the amount of feedback needed would be reduced by the halved plate impedan
ce of parallelled output tubes. But it sounds like your amp plays into typical 8 ohm speakers with
good results, which makes me even more curious about your design. And have you tried your amp with,
say, 8-10 dB of nfb?
Thanks, Tom Sylvester trs@carlsmith.com
=========================================================================
From: "PEARL Cust Serv" <custserv@pearl-hifi.com>
Subject: Re: [JN] Feedback in Pentode SE Amps
Date: Fri, 24 Mar 2000 11:30:50 -0700
Source: Sound Digest Archive v02.n494
> Darryl-
> Very interesting and encouraging. Virtually every SE pentode amp I've seen
> (including J C Morrison's "Blackie Box" in SP 14 and Gordon Rankin's
> original 807 amp, as well as a number of designs on the web that 'listers
> have pointed me to) uses global NFB to lower output impedance/increase
> damping factor to something like that seen in triode SE amps. I had
> assumed that this was a necessary evil of pentode amp designs, but the
> amount of feedback needed would be reduced by the halved plate impedance of
> parallelled output tubes. But it sounds like your amp plays into typical 8
> ohm speakers with good results, which makes me even more curious about your
> design. And have you tried your amp with, say, 8-10 dB of nfb?
> Thanks, Tom Sylvester trs@carlsmith.com
===============================
Hi All:
Note that only a few dB of NFB ( 3 to 8) will cause the out Z of a
pentode stage to tumble by an order of magnitude . . . more or less
Best regards,
Bill - PEARL, Inc.
=========================================================================
From: blackie <tubesville@yahoo.com>
Subject: Re: [JN] Feedback in Pentode SE Amps
Date: Sat, 25 Mar 2000 03:32:31 -0800 (PST)
Source: Sound Digest Archive v02.n495
- --- Thomas Sylvester <TRS@carlsmith.com> wrote:
> Very interesting and encouraging. Virtually every
> SE pentode amp I've seen (including J C Morrison's
> "Blackie Box" in SP 14 and Gordon Rankin's original
> 807 amp, as well as a number of designs on the web
> that 'listers have pointed me to) uses global NFB to
> lower output impedance/increase damping factor to
> something like that seen in triode SE amps. I had
> assumed that this was a necessary evil of pentode
> amp designs...
hi tom
i suggest you tune the NFB loop by ear using a
substitution box if you have one, or a multi-position
switch rigged with succesively decreasing
resistors...that's how the NFB in the "blackie box"
was arrived at...
=====
blackie
blackie@tubesville.com
www.tubesville.com
__________________________________________________
Do You Yahoo!?
Talk to your friends online with Yahoo! Messenger.
http://im.yahoo.com
=========================================================================
From: "Darryl Lock" <dklock@ieee.org>
Subject: RE: [JN] Feedback in Pentode SE Amps
Date: Sat, 25 Mar 2000 10:29:09 +1000
Source: Sound Digest Archive v02.n495
>
> >>> "Darryl Lock" <dklock@ieee.org> 03/23/00 06:08PM >>>
> I haven't seen your circuit, but I prefer SE amps without any
> negative feedback.<<<
>
> Darryl-
> Very interesting and encouraging. Virtually every SE pentode amp
> I've seen (including J C Morrison's "Blackie Box" in SP 14 and
> Gordon Rankin's original 807 amp, as well as a number of designs
> on the web that 'listers have pointed me to) uses global NFB to
> lower output impedance/increase damping factor to something like
> that seen in triode SE amps.
Sorry, I was assuming wiring it as UL or triode.
>I had assumed that this was a
> necessary evil of pentode amp designs, but the amount of feedback
> needed would be reduced by the halved plate impedance of
> parallelled output tubes. But it sounds like your amp plays into
> typical 8 ohm speakers with good results,
Well, as I said, I never liked the sound of pentode mode compared to triode.
However, it still worked quite well of course. Easy to try for yourself and
see.
which makes me even
> more curious about your design. And have you tried your amp
> with, say, 8-10 dB of nfb?
No, I'd rather use it in UL mode. I have played around with NFB in PP amps
where it supposedly is always necessary, and never liked it there either.
So, I tend to go for designs that don't use it.
Darryl
=========================================================================
From: "Thomas Sylvester" <TRS@carlsmith.com>
Subject: Re: [JN] Feedback in Pentode SE Amps
Date: Tue, 28 Mar 2000 08:43:59 -1000
Source: Sound Digest Archive v02.n500
Hey Blackie, thanks for the help. I understand that some important circuit parameters will be jumpin
g around when you change the value of that resistor, but unless you can hear a change for the better
, what's the point? I've been carrying around a binder of SE pentode schemos, tube curves and notes
, scratching my head and wondering where to start. I finally decided to just start with the Blackie
Box plan but use 6550Cs and my transformers, then modify it for UL operation, local feedback with
partially inbypassed cathode resistor, glow-tube regulation on the screens &c. Out to keep me out
of trouble for a couple of weeks, anyway . . .
Tom
>>> blackie <tubesville@yahoo.com> 03/25/00 01:32AM >>>
hi tom
i suggest you tune the NFB loop by ear using a
substitution box if you have one, or a multi-position
switch rigged with succesively decreasing
resistors...that's how the NFB in the "blackie box"
was arrived at...
=====
blackie
blackie@tubesville.com
www.tubesville.com
__________________________________________________
Do You Yahoo!?
Talk to your friends online with Yahoo! Messenger.
http://im.yahoo.com
=========================================================================
From: "Danielak, Robert M" <robert.m.danielak@lmco.com>
Subject: RE: [JN] Feedback in Pentode SE Amps
Date: Tue, 28 Mar 2000 16:15:39 -0500
Source: Sound Digest Archive v02.n500
hi tom,
i hear you...
when i was futzing around with my EL-509 amp
see:
http://www.svetlana.com/docs/TechBulletins/technoteNo33.html
it had pretty decent sound without any feedback at all.
made me question my engineering judgement, once again.
obviously, the distortion was not particularly "objectionable".
damping factor was not *too* bad considering it was a pentode
amp (btw: the el509 has pretty low plate resistance for a beam
tube..).
however, the addition of a relatively small amount of NFB
improved (measured) performance significantly
*without* screwing up the sound.
in fact, i could probably convince myself that it sounded
even better.
a word of warning about local feedback via un-bypassed
cathode. although it may linearize the stage to some degree
it also significantly *increases* its output impedance.
this is probably a greater evil....
pentodes are our friends.
sure they may look and act a little funny, but
once you get used to them, they can be a lot of fun
to be around....
have fun,
bob.d.
> ----------
> From: Thomas Sylvester[SMTP:TRS@carlsmith.com]
> Sent: Tuesday, March 28, 2000 1:43 PM
> To: sound@lists.io.com; tubesville@yahoo.com
> Subject: Re: [JN] Feedback in Pentode SE Amps
>
> Hey Blackie, thanks for the help. I understand that some important circuit
> parameters will be jumping around when you change the value of that
> resistor, but unless you can hear a change for the better, what's the
> point? I've been carrying around a binder of SE pentode schemos, tube
> curves and notes, scratching my head and wondering where to start. I
> finally decided to just start with the Blackie Box plan but use 6550Cs and
> my transformers, then modify it for UL operation, local feedback with
> partially inbypassed cathode resistor, glow-tube regulation on the screens
> &c. Out to keep me out of trouble for a couple of weeks, anyway . . .
> Tom
>
> >>> blackie <tubesville@yahoo.com> 03/25/00 01:32AM >>>
>
> hi tom
>
> i suggest you tune the NFB loop by ear using a
> substitution box if you have one, or a multi-position
> switch rigged with succesively decreasing
> resistors...that's how the NFB in the "blackie box"
> was arrived at...
>
> =====
> blackie
> blackie@tubesville.com
> www.tubesville.com
>
> __________________________________________________
> Do You Yahoo!?
> Talk to your friends online with Yahoo! Messenger.
> http://im.yahoo.com
>
=========================================================================
From: blackie <tubesville@yahoo.com>
Subject: Re: [JN] Feedback in Pentode SE Amps
Date: Wed, 29 Mar 2000 03:52:01 -0800 (PST)
Source: Sound Digest Archive v02.n502
- --- Thomas Sylvester <TRS@carlsmith.com> wrote:
> Hey Blackie, thanks for the help. I understand that
> some important circuit parameters will be jumping
> around when you change the value of that resistor,
> but unless you can hear a change for the better,
> what's the point? I've been carrying around a
> binder of SE pentode schemos, tube curves and notes,
> scratching my head and wondering where to start. I
> finally decided to just start with the Blackie Box
> plan but use 6550Cs and my transformers, then
> modify it for UL operation, local feedback with
> partially inbypassed cathode resistor, glow-tube
> regulation on the screens &c. Out to keep me out of
> trouble for a couple of weeks, anyway . . .
> Tom
sounds good
don't want to think TOO much before you build...i have
always learned more by putting iron to solder
the idea is, just use enough feedback to make it sound
"right"...this will vary, of course, depending on the
load (speaker)...
=====
blackie
blackie@tubesville.com
www.tubesville.com
__________________________________________________
Do You Yahoo!?
Talk to your friends online with Yahoo! Messenger.
http://im.yahoo.com
=========================================================================
From: tube@jump.net
Subject: [JN] Feedback, Phase Distortion, and Emitter Followers
Date: Tue, 06 Jun 2000 16:03:11 -0500
Source: Sound Digest Archive v02.n568
PEARL Cust Serv wrote:
> Hi, tube@jump.net wrote
>
> > . . . . .but suffice it to say that Matti Otala
> > proved many years ago that feedback absolutely cannot make distortions
> > go away, it can only transform amplitude distortions into phase
> > distortions.
>
> Can you provide references here?
> This is VERY interesting particularly since I just dreamed up a way of
> measuring the phase of individual harmonic components as a function of both
> swept frequency and stepped amplitude.
> I've been wanting to do this for years and some recent hard study of
> Richard Heyser finally booted me in the a** to think this thru.
> So, Otala's work is very relevant at this point in my investigations,
> particularly in view of the work I watched Meinter do a few years ago wrt
> the audibility of jitter in digital circuitry. This is, after all, an
> uncommonly pernicious form of phase distortion.
> Tia . . . .
>
> Best regards,
> Bill - PEARL, Inc.
Sure. There was a discussion on all subjects in The Audio Critic, 1979,
Vol-2 #1 and Vol-2 #2, including a long discussion on feedback in #1,
with Mitch Cotter, Julius Futterman, Stew Hegeman, Matti Otala, Andy
Rappaport, Max Wilcox, Bruce Zayde, and the editor Peter Aczel. In the
Vol-2 #2, Peter said that Otala would deliver the paper on Feb 25,
1980, at the AES in London. He added that:
"The paper presents rigorous mathematical proof, for the most
generalized, all-inclusive case, that feedback cannot make amplifier
distortions go away; all it can do is change one kind of distortion
into another...
"By the application of feedback, the amplitude nonlinearities of the
open loop are converted into phase nonlinearities of the closed loop...
"In the typical feedback amplifier, the amplitude of the audio signal
phase-modulates the high-frequency components of the signal.
Furthermore, any amplitude intermodulation distortion in the open loop
is converted into phase intermodulation distortion in the closed
loop. What about TIM, alias SID? It turns out that it (he?) is a limit
case of this feedback-generated phase modulation effect, with all
shades of gray possible before the actual black eruption occurs. None
of this shows up on standard tests."
So, somewhere in the Journal of the Audio Engineering Society, after
Feb. 1980, you should find some articles by Dr. Matti Otala on
feedback. Apparently he was going to add further articles on feedback,
including methods to test the level of phase modulation distortion,
but I don't know for sure whether he did or not.
I might as well add a bit of what I recently found. As you may
remember, I am trying to make a variable frequency 3-phase generator
(I liked your idea, except that it didn't look like it could be used
in a variable frequency circuit). If you have two sine waves of the
same frequency, but with one of the waves "shifted forward" by one
quarter wavelength (90 degrees), you have sine and cosine signals. You
can then place a potentiometer between these two waves, and the output
is a third wave of the same frequency which varies from 0 to 90 degrees
as you turn the pot from the sine wave to the cosine wave.
The main point is that when you add a sine wave to another sine wave of
the same frequency, the result is a sine wave which is PHASE SHIFTED
from the first two waves. Furthermore, the result depends on the
amplitude of the two original sine waves. If the sine wave becomes a
little larger than the cosine wave, then the output from the pot will
phase shift towards the sine wave. In other words, any AMPLITUDE errors
in the sine and cosine waves become PHASE errors in my 3-phase outputs,
shifting them back and forth in phase. Instead of having 3 sine waves
each 120 degrees apart, I suddenly have a second wave 110 degrees from
the first wave, and a third wave 130 degrees from the second. I would
never have known this without trying to design the 3-phase generator.
This gave me a way, for the first time, a way to visualize what must be
happening in a feedback amp. When the feedback signal is added to the
original signal, it transforms any amplitude variations between the two
signals into varying phase-shifts in the output, just as it does in my
3-phase generator.
I should probably try to do a better job of explaining my ideas on
transistors and feedback as well, given that MULTIPLE people asked me
if I had ever heard of emitter followers! Okay, given the circuits
below:
The first circuit is a normal emitter follower, with the output at B.
Suppose that the base-emitter voltage (from B to E) is the normal 0.7V,
but that the load suddenly pulls E down 2 more volts (speakers, which
store and release energy, WILL try to do this on occasion). Let's say
that half of this 2V is dropped across the resistor from A to B. This
means that the base-emitter voltage is now 1.7V, which will cause a
tremendous increase in current from the transistor. This increase in
current will "fight" or resist any attempt by the speaker to lower the
voltage at E.
| |
| <
| > LOAD
| <
| >
| C |
| -----|
| | |
| > |
| < |
/ > /
A B |/ | |/
--\/\/---| NPN --\/\/--O--| NPN
|\ A B |\
\ \
| |
|--- E |--- E
| |
< |
> LOAD |
< |
> |
| |
GND GND
In the second circuit, the base to emitter voltage is again 0.7V. Now
the load will RAISE the collector voltage at C by 2V. Let's say that
the resistor from C to B equals the resistor from A to B. Therefore,
half of this 2V will be dropped across the resistor from C to B,
raising the voltage at B by 1V. This again means that the base to
emitter voltage will increase to 1.7V, again causing a huge increase
in current that resists the effort by the load to raise the voltage.
This is the classic negative feedback connection: The signal from the
output is added to the input in such a way that if the load tries to
raise the output voltage, feedback makes the transistor try to lower
it back down. Because the load is not connected to either the base or
the emitter, we must ADD a feedback connection from the load to the
base. Notice, however, that as far as the transistor is concerned,
there is no difference whatsoever between these two circuits. In both
cases, the load changes the base to emitter voltage, and it is this
change in B-E voltage ALONE that causes the transistor to resist any
attempts by the load to change the voltage. The only difference
between these two circuits is that because the load is directly
connected to the emitter in the emitter follower circuit, we do not
need to ADD a negative feedback connection to have negative feedback.
The negative feedback connection exists automatically. In both
circuits the transistor is COMPLETELY DEPENDENT on negative feedback
to get a low output impedance--that is, an impedance which "fights"
or resists any attempt by the load to change the output voltage.
A speaker not only stores and releases energy, it also transforms
sound waves which reflect back into the speaker into signals, and it
has a very non-linear impedance, which also varies the output voltage.
In amplifiers which rely on feedback to get a low output impedance,
100% of these energy/impedance effects will be converted into phase
distortions. Period. No exceptions. All deviations from what a perfect
output device going into a perfect 8 ohm resistor would produce are
converted into phase distortions.
A transformer coupled triode amplifier does not have this problem.
Guido brought up the fact that they have type 1 and type 2 feedbacks,
with type 1 being the type discussed above, and type 2 being what you
find in a triode amp due to the low output impedance. The 3-phase
generator analogy has helped me here as well, because I finally see
that the difference is that the low plate resistance of a triode does
NOT produce an additional signal which can mix with the input signal.
Without this additional signal, there is no way for the triode amp to
phase modulate the signal, thereby causing phase distortions. For
myself, therefore, I am going to say that there actually two types of
LOW IMPEDANCES, rather than two types of feedback. A "triode" low
impedance relies on the low impedance of the output device to fight
or resist any changes in voltage. A "feedback" low impedance relies
on negative feedback to convert any changes in the output into changes
in phase. However, there is nothing special about my point of view.
Any view will work, as long as you understand exactly what the view
means and how the basic processes actually work.
Does this mean that all feedback and all cathode followers are bad?
No. As long as there are no amplitude variations, it should be
difficult or impossible for feedback to convert what does not exist
into phase distortions. A constant low impedance load, handled by a
cathode follower, should be mostly okay (although CF's have other
problems which can appear if the circuit does something wrong). Also,
a small amount of feedback can cause fairly large changes in
impedance and frequency while not producing too much phase distortion.
As for the "all or nothing" question, meaning only lots of feedback or
none at all, there is obviously something going on that makes this a
valid point. However, quoting from The Audio Critic article again:
Stew Hegeman: Western Electric 300B's. At the time I was working for
the Bell System, I used to hear that stuff, and I used to say, Oh God,
if only I could make something like that, that sounded like that, in
my living room. Okay. Bode, Dr. Black, they came up with feedback;
and commercially, Western Electric went to pentodes, pentodes with
feedback. Various other circuits have come up. But they never sounded
quite as good as I remember those triodes.
Julius Futterman: That's nostalgia.
Hegeman: I'm sure that's nostalgia.
Mitch Cotter: You were at Bell--you recall the caution with which they
exercised themselves about 12 dB of feedback, 8 dB of feedback?
Hegeman: Oh yes, oh yes.
[later]
Hegeman: ... This 20, 30 dB feedback kind of thing, you're just
building yourself into a hole.
I must say, it's fun to read the words of the guys who actually lived
through all of this stuff!
As for feedback, who knows? It may even be that the situation which
feedback is used in determines the right amount. Given Al Marcy's
experiences with small amounts of feedback, however, I will be happy
to try small amounts as well as large.
Phil
=========================================================================
From: TubeGarden@aol.com
Subject: Re: [JN] Feedback, Phase Distortion, and Emitter Followers
Date: Tue, 6 Jun 2000 21:11:51 EDT
Source: Sound Digest Archive v02.n569
In a message dated 6/6/00 2:09:21 PM US Mountain Standard Time, tube@jump.net
writes:
> Given Al Marcy's
> experiences with small amounts of feedback, however, I will be happy
> to try small amounts as well as large.
Hi Feedback Freaks!
My latest exercise was with Positive Current FB, on a hint from St. Bench.
On my single stage SV83, I put a small R (< 1 ohm) between the parafeed OPT
secondary and ground. The speaker returned to ground.
The Cathode Bias Network was tied in above the R.
The OPT primary decoupling cap was tied in above the CBN.
I tuned the R by listening. I tested form 0.25 ohms to 3 ohms. I ended with a
hellish 0.666, parallel 1 and 2 ohms.
This Lawrence Welk circuit ( a one and a two...) gave 0.1 dB of boost at 1KHz
and 1.1 dB at 100 Hz.
This sounded fine.
___
I have since replaced the OPT with an E-P 3634 1:1 IT driving a 2A3 simple SE
into a ubt-3. Deleted the plusI FB.
The only FB is the 1 ohm R under each CBN I use to balance the current
between the SV83 and the 2A3 on each channel. The idea is to minimize current
demand changes.
This sounds even finer.
Happy Ears!
Al B^}
=========================================================================
From: "Michael Cameron" <mncameron@worldnet.att.net>
Subject: Re: [JN] Fender Princeton OPT, (OMT)
Date: Mon, 25 Jan 1999 06:21:49 -0800
Source: Sound Digest Archive v02.n011
- -----Original Message-----
From: StepHydro@aol.com <StepHydro@aol.com>
To: sound@lists.io.com <sound@lists.io.com>
Date: Monday, January 25, 1999 4:47 AM
Subject: Re: [JN] Fender Princeton OPT, (OMT)
Carron asked:
>A few days ago, there were a number of posts about the Subject transformer
>available form Angela. I lookedat the site, and there is a 10W OPT
designated
>Champ. Is this the one?
>
>Yes, this is the one.
>Anyone have any idea of the current capapacity of that OPT? How about the
>insulation voltage withstand rating?
Fender does not give out ratings on their iron.
I have used one of these OPT in a SE guitar amp running 350v B+ at anywhere
from 35 to 70ma for a couple of years now. Also used this OPT in a SE 6DN7
audio amp with fine results at 330v at 25-30ma.
Michael
=========================================================================
From: StepHydro@aol.com
Subject: Re: [JN] Fender Princeton OPT, (OMT)
Date: Mon, 25 Jan 1999 07:34:18 EST
Source: Sound Digest Archive v02.n011
A few days ago, there were a number of posts about the Subject transformer
available form Angela. I lookedat the site, and there is a 10W OPT designated
Champ. Is this the one?
Anyone have any idea of the current capapacity of that OPT? How about the
insulation voltage withstand rating?
Cheers/Carron
=========================================================================
From: "Eric Weitzman" <eweitzman@acm.org>
Subject: [JN] ferrite bead specifications
Date: Fri, 25 Aug 2000 07:42:36 -0700
Source: Sound Digest Archive v02.n641
Which type/size/"rating" ferrite beads have people been using in place of
grid stoppers?
They seem to be specified as "Z at 100mHz", rated DC current, and DCR.
How do you know their Z at lower frequencies, say, at 1mHz. Isn't it
important to know that the Z is high at lower frequencies too, since you
can't determine (and thus, don't know) the frequency of parasitic
oscillations without a very high-frequency scope? Just go for the higher Z
ratings at 100mHz?
And why is there a DCR? Wouldn't that just be a function of the wire going
through the bead?
Finally, aren't ferrites peculiar ceramic/metal lattices that can be made
from dozens of different compounds resulting in different properties? Why
hasn't there been an audiophile debate on the merits of the "airy" sound of
nickel-zinc ferrite versus the "authoritative bottom end" of lithium
ferrite?
- - Eric
=========================================================================
From: TubeGarden@aol.com
Subject: Re: [JN] ferrite bead specifications
Date: Fri, 25 Aug 2000 12:46:59 EDT
Source: Sound Digest Archive v02.n641
In a message dated 8/25/00 7:45:02 AM US Mountain Standard Time,
eweitzman@acm.org writes:
> Finally, aren't ferrites peculiar ceramic/metal lattices that can be made
> from dozens of different compounds resulting in different properties?
Greets!
I get mine for a dollar a dozen out of a bin at Apache Reclamation.
I pick out visual pairs and so far, they all sound the same :)
Happy Ears!
Al B^}
=========================================================================
From: evaguido <EvaGuido@iaehv.nl>
Subject: Re: [JN] ferrite bead specifications
Date: Fri, 25 Aug 2000 17:28:45 +0200
Source: Sound Digest Archive v02.n641
At 07:42 25/08/2000 -0700, Eric Weitzman wrote:
>Which type/size/"rating" ferrite beads have people been using in place of
>grid stoppers?
>
>They seem to be specified as "Z at 100mHz", rated DC current, and DCR.
Most among them, yes
>How do you know their Z at lower frequencies, say, at 1mHz.
well, 1 mHz is near DC so........
Serious now. Philips and Murata publish Z as function f frequency, biased
as well
>Isn't it
>important to know that the Z is high at lower frequencies too, since you
>can't determine (and thus, don't know) the frequency of parasitic
>oscillations without a very high-frequency scope? Just go for the higher Z
>ratings at 100mHz?
You should now at which frequency the circuit tends to oscillate, in order
to find the right ferrite
>And why is there a DCR? Wouldn't that just be a function of the wire going
>through the bead?
Yes
>Finally, aren't ferrites peculiar ceramic/metal lattices that can be made
>from dozens of different compounds resulting in different properties?
Yes
>Why
>hasn't there been an audiophile debate on the merits of the "airy" sound of
>nickel-zinc ferrite versus the "authoritative bottom end" of lithium
>ferrite?
:-)
To be done, I guess. Do you have experiences ?
Some ferrites are constructed as L//C, such that they show very high
impedance at a certain freq. Smaller bandwidth in return, but very nice,
sometimes
Guido
>- Eric
>
>
>
=========================================================================
From: Cuno Snoeren <c.snoeren@tip.nl>
Subject: [JN] Ferrite ring on speakercable
Date: Thu, 06 Jan 2000 21:30:59 +0100
Source: Sound Digest Archive v02.n389
Hi all
I wonder if it makes sense to have a ferrite ring around the speaker-
cables.
I mean the rings that you see on printercables and mainscables of your
computer.
Does it make any sense at high current low impedance sources like with
speakercables??
O.k. I do understand the use of it on interlinks and mains cables......
It filters HF without disturbing the signal (like some netfilters can do
with the dynamics of your audio system)
Greetings,Cuno Snoeren
http://www.ariel.club.tip.nl
http://www.triode.club.tip.nl
Cuno Snoeren
=========================================================================
From: Cuno Snoeren <c.snoeren@tip.nl>
Subject: [JN] Ferrite ring on speakercables
Date: Thu, 06 Jan 2000 23:17:38 +0100
Source: Sound Digest Archive v02.n389
Hi all
I wonder if it makes sense to have a ferrite ring around the speaker-
cables.
I mean the rings that you see on printercables and mainscables of your
computer.
Does it make any sense at high current low impedance sources like with
speakercables??
O.k. I do understand the use of it on interlinks and mains cables......
It filters HF without disturbing the signal (like some netfilters can do
with the dynamics of your audio system)
Greetings,Cuno Snoeren
http://www.ariel.club.tip.nl
http://www.triode.club.tip.nl
=========================================================================
From: Richard C Nevill <rnevill@is.dal.ca>
Subject: Re: [JN] Ferrite ring on speakercables
Date: Fri, 7 Jan 2000 16:45:57 -0400 (AST)
Source: Sound Digest Archive v02.n391
I found it added a congestion to the sound that wasn't there before I
added the things. After taking them away the focus reappeared.
Yer milage may vary,
Cheers
Richard Nevill
On Fri, 7 Jan 2000, evaguido wrote:
> Hi Cuno,
>
> Basically it could make sense. I do not know if you read my range of
> articles, but I stated there that every elecrically long cable acts as an
> antenna and therefore maight carry RF currents as if it were a monopole
> antenna.
>
> Ususally speaker wires are few meters only so they start receiving at say
> 10 MHz.
>
> Once you start applying ferrte I guess you should be consequent.....
>
> regards
>
> Guido
>
> At 23:17 06/01/00 +0100, Cuno Snoeren wrote:
> >Hi all
> >
> >I wonder if it makes sense to have a ferrite ring around the speaker-
> >cables.
> >I mean the rings that you see on printercables and mainscables of your
> >computer.
> >Does it make any sense at high current low impedance sources like with
> >speakercables??
> >
> >O.k. I do understand the use of it on interlinks and mains cables......
> >It filters HF without disturbing the signal (like some netfilters can do
> >with the dynamics of your audio system)
> >
> >Greetings,Cuno Snoeren
> >http://www.ariel.club.tip.nl
> >http://www.triode.club.tip.nl
> >
> >
>
=========================================================================
From: evaguido <EvaGuido@iaehv.nl>
Subject: Re: [JN] Ferrite ring on speakercables
Date: Fri, 07 Jan 2000 18:46:50 +0100
Source: Sound Digest Archive v02.n391
Hi Cuno,
Basically it could make sense. I do not know if you read my range of
articles, but I stated there that every elecrically long cable acts as an
antenna and therefore maight carry RF currents as if it were a monopole
antenna.
Ususally speaker wires are few meters only so they start receiving at say
10 MHz.
Once you start applying ferrte I guess you should be consequent.....
regards
Guido
At 23:17 06/01/00 +0100, Cuno Snoeren wrote:
>Hi all
>
>I wonder if it makes sense to have a ferrite ring around the speaker-
>cables.
>I mean the rings that you see on printercables and mainscables of your
>computer.
>Does it make any sense at high current low impedance sources like with
>speakercables??
>
>O.k. I do understand the use of it on interlinks and mains cables......
>It filters HF without disturbing the signal (like some netfilters can do
>with the dynamics of your audio system)
>
>Greetings,Cuno Snoeren
>http://www.ariel.club.tip.nl
>http://www.triode.club.tip.nl
>
>
=========================================================================
From: "Stewart Ono" <audiodir@gte.net>
Subject: [JN] Re: Ferrites
Date: Fri, 14 Jan 2000 08:38:57 -1000
Source: Sound Digest Archive v02.n403
I've had relatively good results sticking ferrites on the legs of FR diodes
and all switching devices in general. Seems to cut down on the glare and
smooth out the sound. Trouble is, there are many types of ferrites with
different properties. Check out the Fair-rite company's website. They can
also custom make them, although they are not cheap unless you're buying
large quantities. The ferrites are particularly effective in digital gear,
and I sprinkle them quite liberally throughout the p/s circuit.Of course,
now with this DVD stuff and all it's SMD's, it's a hell of a lot harder.
Stu
=========================================================================
From: Francois Yves Le Gal <flegal@free.fr>
Subject: Re: [JN] Ferrograph Model 64 4 Track Reel to reel.
Date: Thu, 04 Jan 2001 11:40:54 +0100
Source: Sound Digest Archive v02.n774
At 18:14 04/01/01 +0800, Michael (Mick)Maloney wrote:
>Can anyone point me to a manual and parts to get this oldtimer back on the
>block.
A good start would be http://www.morphet.org.uk/ferro/ or
http://www.gwest56.freeserve.co.uk/ferrograph/
=========================================================================
From: Francois Yves Le Gal <flegal@free.fr>
Subject: RE: [JN] Ferrograph Model 64 4 Track Reel to reel.
Date: Thu, 04 Jan 2001 13:26:24 +0100
Source: Sound Digest Archive v02.n774
At 22:32 04/01/01 +1100, Bart Shepherd \(Home\) wrote:
>Anything similar around for a Revox G36 tube number? I have seen the AA
>"greening" stuff.
http://www.megabaud.fi/~jtolonen/ga/revox/revox.html
=========================================================================
From: "Michael (Mick)Maloney" <supra@cantech.net.au>
Subject: [JN] Ferrograph Model 64 4 Track Reel to reel.
Date: Thu, 04 Jan 2001 18:14:37 +0800
Source: Sound Digest Archive v02.n774
- --=======591E5EDF=======
Content-Type: text/plain; charset=us-ascii; x-avg-checked=avg-ok-3A2713C0
Spotted what looked like a mint Ferrograph Model 64 4 Track reel tape
machine in a secondhand shop.
Couldn't help myself and paid $50 for it.
Pulled the nice teak cabinet off and it is in very good condition, with the
usual great engineering from that era. And full of Telefunken tubes!
No obvious head wear but age has caught up with the rubber capstan round
belt and it was in bits.
Can anyone point me to a manual and parts to get this oldtimer back on the
block.
Have you heard this one Allen?
MickM
- --=======591E5EDF=======
Content-Type: text/plain; charset=us-ascii; x-avg-checked=avg-ok-3A2713C0
- ---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.225 / Virus Database: 107 - Release Date: 12/22/00
- --=======591E5EDF=======--
=========================================================================
From: "Bart Shepherd \(Home\)" <bart.s@bigpond.net.au>
Subject: RE: [JN] Ferrograph Model 64 4 Track Reel to reel.
Date: Thu, 4 Jan 2001 22:32:52 +1100
Source: Sound Digest Archive v02.n774
Anything similar around for a Revox G36 tube number? I have seen the AA
"greening" stuff.
Thanks,
Bart
- -----Original Message-----
From: owner-sound@lists.io.com [mailto:owner-sound@lists.io.com]On
Behalf Of Francois Yves Le Gal
Sent: Thursday, 4 January 2001 9:41 PM
To: sound@lists.io.com
Subject: Re: [JN] Ferrograph Model 64 4 Track Reel to reel.
At 18:14 04/01/01 +0800, Michael (Mick)Maloney wrote:
>Can anyone point me to a manual and parts to get this oldtimer back on the
>block.
A good start would be http://www.morphet.org.uk/ferro/ or
http://www.gwest56.freeserve.co.uk/ferrograph/
=========================================================================
From: Kurt Steffensen <kurt-steffensen@teliamail.dk>
Subject: [JN] FESTIVAL NEWS
Date: Sun, 23 Jul 2000 22:26:56 +0200
Source: Sound Digest Archive v02.n609
Gentlemen.
Thing keeps developing at this side.
Since the last news bulletin , more people ( Thorbjørn and Peter
Sikking , for instance :-) , and equipment has signed up.
Matjiis De Vries will come with his exciting tube regulated sub
miniature RIAA , and he might even drag some Altec Speakers up here.
Hugh Dean will send his interesting little solid state Amp.
Jens Posselt will come with his new easy driven speakers.
Michael Ulbrich will bring his well known OPT's.
Gerhard Dierkes will bring his version of the high praised Siren Song.
Hartmut Quaschik will bring some Kaneda's , and offers a workshop on
this issue.
Hiroshi Ito and Lynn Olson have offered one of the famous DAC
attenuators , as a prize or something , at the festival :-)
Bless these two Gentlemen.
David Crittle , that good and nice Aussie , has made a box of stuff for
the Joes :-)
Morten will bring some amplifiers and tubes from JJ Electronics.
Blackie says he just might come , and he says he will try to talk to
Slagle in to it... :-)
I cross my fingers for this to happen.
( Imagine these two guys , trying to drag one of Slagles amps in to a
plan....!
I would not be surprised if the security called the Fed's anti terror
organization. Most look like a nuclear bomb to them )
Ortofons Pick Up Expert and chief engineer Per Windfeld, will attend
Saturday. :-))
He asks me to suggest an idea on which he can base his lecture and
presentation of the PU's.
What do you suggest , Joes ?
Considering that he is one of the few real experts in this matter , left
on earth , and that Ortofon has probably the longest history
and experience to drag from , I think it would be plain stupid if we do
not to prepare a bunch of questions , to this good man.
He was thrilled to read the list with all the tube equipment , and would
like to play a lot of them smashing Ortofons through all the available
gear.
- - Couldn't agree more with him :-)
He is a genuine Joe , Joes , as he uses valve amplifiers himself at
home.
I hope they will offer some PU's , at a special price to us Joes during
the Festival. I will do my best to talk them in to that.
I am desperate for one of the late MC's..... ;-)
Per Windfeld has asked me to kindly let him know exactly what turntables
, and in particular which PU arms we will let him use.
Please , report that back to me , in order to perform the best possible
auditions.
Ortofons homepage:www.ortofon.com
I will try to get some firms that deals with components and parts ,
talked into offer us Joes some items at special festival discount rates
, during the weekend.
So far I have managed that with three companies , that I believe were
very interesting.
That is PLITRON output transformers , Marshall 1" condensator
microphones , Antique Audio Lab amplifiers and OPT. ( All of these are
20% of list , during the days )
I wanted to hear these myself , anyhow , and if I am happy with their
products , I hope to become their agent in Denmark , later this year.
Further I will contact Chesky for genuine 24/96 DVD disc's. Maybe their
Danish distributor , will offer these at "special festival discounts"
:-)
Please , feel free to contact some of your own , and tell them about the
thing. The "carrot" for these companies are not the possible sale in it
self , but the opportunity
to find dealers or agents for their products , and to present these
products to all us nice folks.
If their products are good and interesting , I for one , would not mind
dealing with that company after the festival.
And I am sure many Joes , feels the same way.
If they agree , we will arrange a little stand with their products , and
take orders from the Joes.
In order to purchase any of these products , you do not need to be at
the festival. I will try to keep you all updated , and take orders from
all the unhappy Joes
at home.
But these offers are only good to Joelisters.
If you want me to publish more about these , above products , and the
prices , please let me know.
Or simply visite their websites.
I will also try to get some genuine DVD disc's for the weekend.
I am here thinking of Chesky 24/96 and "Arthouse" music performances ,
though I doubt that these last are genuine
24/96.
As far as I am informed , the "Classic records" company , does not carry
any genuine 24/96 ?
( They seems to have 20/96 copies of old analogue master tapes ,
though.)
I will have a talk with Chesky and the Danish distributor.
I hope we can compare the same recording on vinyl , CD and DVD.
I think that is all for now , if you have any comments or questions ,
please do not hesitate to contact me.
Only 12 days to impact :-)
Get ready , folks.
( Playing in the background Richard Strauss "Zarathusta" , or the clock
theme from Pink Floyds "Dark side of the moon" )
- - Sincerely Kurt Steffensen.
=========================================================================
From: evaguido <EvaGuido@iaehv.nl>
Subject: Re: [JN] FESTIVAL NEWS
Date: Mon, 24 Jul 2000 22:01:20 +0200
Source: Sound Digest Archive v02.n609
dear Kurt,
Every time you mail with an update on the festival my heartbeat doubles
you wrote:
>Michael Ulbrich will bring his well known OPT's.
and
>So far I have managed that with three companies , that I believe were
>very interesting.
>That is PLITRON output transformers , Marshall 1" condensator
>microphones , Antique Audio Lab amplifiers and OPT.
So that adds for an eventual transformer shoot-out. Anyone interested ?
Did you (Kurt) manage to arrange an overhead projector for the lectures ?
While talking on 24 bits / 96 kHz: unfortunately my 2 DACs do not support
96 kHz audio......
>Only 12 days to impact :-)
>Get ready , folks.
:-)
Guido
=========================================================================
From: Kurt Steffensen <kurt-steffensen@teliamail.dk>
Subject: Re: [JN] FESTIVAL NEWS
Date: Tue, 25 Jul 2000 16:34:30 +0200
Source: Sound Digest Archive v02.n609
evaguido wrote:
> dear Kurt,
>
> Every time you mail with an update on the festival my heartbeat doubles
I will be more careful with these in the future , Guido.. ;-)
I will however , post one more next week. But that one will be the last.
> So that adds for an eventual transformer shoot-out. Anyone interested ?
Well , we will have a decent selection of OPT's.
> Did you (Kurt) manage to arrange an overhead projector for the lectures ?
Unfortunately , I won't know about that before next week..
People is on vacation , and I myself are going to the "Langeland Music
Festival" this weekend.
> While talking on 24 bits / 96 kHz: unfortunately my 2 DACs do not support
> 96 kHz audio......
Ah , well. We will use them with the CD players.
> >Only 12 days to impact :-)
> >Get ready , folks.
10 days , that is..... Uh... :-)
BTW , I got Steves bat amp , yesterday.
Wait to you see this little baby , Joes... I think that Steve message about
all these sub miniatures , gets through just perfect.
Use them sub's , Joes.. They are out there in mass.....
6948 , 6111 , 6BF7 - just to mention a few of the good ones.
Though he just made the thing , on his way back home from work , it is rather
cool , in a funny way..
The schematic is on SB's homepage.
Thanx , Steve :-)
I think we will develop an outstanding sub pre amp , based on this bat amp of
Steves. I will get back to you about that after the summer Steve , and all.
See many of you soon :-)
( I LOVE that :-)
- - Kurt
>
>
> :-)
>
> Guido
=========================================================================
From: evaguido <EvaGuido@iaehv.nl>
Subject: Re: [JN] FESTIVAL NEWS
Date: Tue, 25 Jul 2000 20:41:57 +0200
Source: Sound Digest Archive v02.n609
At 16:34 25/07/2000 +0200, Kurt Steffensen wrote:
>Well , we will have a decent selection of OPT's.
So, my question again, what about a universal interface to simplify
exchanging trannies ? I paste my proposal below
- -------------------
- - Transformer
Primary: male 4 mm banana connectors
Anode: Red
B+: other color, prerably Black
Secondary: female 4 mm banana connectors
0: Black
4 ohm: Blue, Preferably
8 ohm: Red, preferably
- - Amplifier female 4 mm banana connectors
Anode: Red
B+: other color, prerably Black
My 300b by preference has additional 100mA slow-blow fuse in series with
the B+.
- ----------------------------
>> Did you (Kurt) manage to arrange an overhead projector for the lectures ?
>
>Unfortunately , I won't know about that before next week..
OK
>People is on vacation , and I myself are going to the "Langeland Music
>Festival" this weekend.
Which I guess is not bad idea in order to get the battery charged a little,
at your side
Guido
=========================================================================
From: S.C.Busbridge@bton.ac.uk
Subject: RE: [JN] FESTIVAL WEATHER REPORT
Date: Mon, 30 Jul 2001 14:56:26 +0100
Source: Sound Digest Archive v02.n936
Hi Kurt
Yesterday here in the UK it reached 32 C in some parts of the south.
Kurt, you have arranged everthing so well, can you please arrange for the
temperature to drop a bit? :-) You know, with all those valves....
Best,
Simib
Simon Busbridge, BSc(Hons) PhD CPhys MInstP
School of Engineering
University of Brighton
Lewes Road
Moulsecoomb
Brighton BN2 4GJ
UNITED KINGDOM
Tel: 0044 (0)1273 642542
Fax: 0044 (0)1273 642327/642301
e-mail: s.c.busbridge@bton.ac.uk, scbusbridge@hotmail.com
Audio www site: http://audio.eng.bton.ac.uk
> ----------
> From: Kurt Steffensen[SMTP:kurt@pappagallo.dk]
> Sent: 30 July 2001 14:31
> To: sound@io.com
> Subject: [JN] FESTIVAL WEATHER REPORT
>
> For the past 2-3 weeks the weather has acted very nice indeed.
> Seems like it will last.
>
> The sun is shining from a blue heaven , and the temparature is
> from + 22 to 30 degrees Celcious.
> 22 to 25 is fine with me. But close to 30 is a little to much of the good
> stuff for vikings.
>
> There is still room for a few persons , if anyone wishes to go.
>
> I can hardly wait :-)
>
> See you all soon.
>
> - Kurt
>
>
=========================================================================
From: "Kurt Steffensen" <kurt@pappagallo.dk>
Subject: [JN] FESTIVAL WEATHER REPORT
Date: Mon, 30 Jul 2001 15:31:14 +0200
Source: Sound Digest Archive v02.n936
This is a multi-part message in MIME format.
- ------=_NextPart_000_002A_01C1190C.AB27D1A0
Content-Type: text/plain;
charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable
For the past 2-3 weeks the weather has acted very nice indeed.
Seems like it will last.
The sun is shining from a blue heaven , and the temparature is
from + 22 to 30 degrees Celcious.
22 to 25 is fine with me. But close to 30 is a little to much of the =
good stuff for vikings.
There is still room for a few persons , if anyone wishes to go.
I can hardly wait :-)
See you all soon.
- - Kurt
- ------=_NextPart_000_002A_01C1190C.AB27D1A0
Content-Type: text/html;
charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
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<META content=3D"text/html; charset=3Diso-8859-1" =
http-equiv=3DContent-Type>
<META content=3D"MSHTML 5.00.2614.3500" name=3DGENERATOR>
<STYLE></STYLE>
</HEAD>
<BODY bgColor=3D#fffbf0>
<DIV><FONT face=3DArial size=3D2>For the past 2-3 weeks the weather has =
acted very=20
nice indeed.</FONT></DIV>
<DIV><FONT face=3DArial size=3D2>Seems like it will last.</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=3DArial size=3D2>The sun is shining from a blue heaven , =
and the=20
temparature is</FONT></DIV>
<DIV><FONT face=3DArial size=3D2>from + 22 to 30 degrees =
Celcious.</FONT></DIV>
<DIV><FONT face=3DArial size=3D2>22 to 25 is fine with me. But close to =
30 is a=20
little to much of the good stuff for vikings.</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=3DArial size=3D2>There is still room for a few persons , =
if anyone=20
wishes to go.</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=3DArial size=3D2>I can hardly wait =
:-)</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=3DArial size=3D2>See you all soon.</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=3DArial size=3D2>- Kurt</FONT></DIV>
<DIV> </DIV></BODY></HTML>
- ------=_NextPart_000_002A_01C1190C.AB27D1A0--
=========================================================================
From: "Kurt Steffensen" <kurt-steffensen@teliamail.dk>
Subject: Sv: [JN] FESTIVAL WEATHER REPORT
Date: Mon, 30 Jul 2001 20:22:24 +0200
Source: Sound Digest Archive v02.n937
> Kurt, you have arranged everthing so well, can you please arrange for the
> temperature to drop a bit? :-) You know, with all those valves....
Consider it done.
;-)
=========================================================================
From: evaguido <EvaGuido@iaehv.nl>
Subject: Re: Sv: [JN] FESTIVAL WEATHER REPORT
Date: Tue, 31 Jul 2001 10:08:10 +0200
Source: Sound Digest Archive v02.n937
Hi,
Maybe some among us can bring some P-type tubes to compensate for the
generated heat.
Guido (counting down)
At 20:22 30-7-01 +0200, Kurt Steffensen wrote:
>> Kurt, you have arranged everthing so well, can you please arrange for the
>> temperature to drop a bit? :-) You know, with all those valves....
>
>Consider it done.
>;-)
>
>
=========================================================================
From: MHuber@t-online.de (Manfred Huber)
Subject: Re: Sv: [JN] FESTIVAL WEATHER REPORT
Date: Tue, 31 Jul 2001 18:15:09 +0200
Source: Sound Digest Archive v02.n938
Kurt,
>> Kurt, you have arranged everthing so well, can you please arrange for the
>> temperature to drop a bit? :-) You know, with all those valves....
>
>Consider it done.
I really hope you are successful! Right now I'm melting away at about 35°C!
I just finished preparation of the overhead pojector foils for the PSU workshop.
In only 26 hours me and my family will leave for Arhus!
CU all there!
Manfred
- ------------------
Manfred Huber
MHuber@t-online.de
- ------------------
=========================================================================
From: evaguido <EvaGuido@iaehv.nl>
Subject: Re: Sv: [JN] FESTIVAL WEATHER REPORT
Date: Tue, 31 Jul 2001 18:59:57 +0200
Source: Sound Digest Archive v02.n938
Hi Manfred
Just finished my sheets as well. Temperature unknown, praying for CPU fan
working right now......
Guido & Eva will leave after 36 jours from now
Travel safe, you all
Guido
At 18:15 31-7-01 +0200, Manfred Huber wrote:
>Kurt,
>
>>> Kurt, you have arranged everthing so well, can you please arrange for the
>>> temperature to drop a bit? :-) You know, with all those valves....
>>
>>Consider it done.
>
>I really hope you are successful! Right now I'm melting away at about 35°C!
>I just finished preparation of the overhead pojector foils for the PSU
>workshop.
>In only 26 hours me and my family will leave for Arhus!
>
>CU all there!
>
>Manfred
>
>
>------------------
>Manfred Huber
>MHuber@t-online.de
>------------------
>
=========================================================================
From: Conrad Drake <conrad@directwest.iinet.net.au>
Subject: [JN] FESTIVAL WEATHER REPORT
Date: Tue, 31 Jul 2001 21:19:20 +0800
Source: Sound Digest Archive v02.n938
sound-digest wrote:
>
> Date: Mon, 30 Jul 2001 14:56:26 +0100
> From: S.C.Busbridge@bton.ac.uk
> Subject: RE: [JN] FESTIVAL WEATHER REPORT
>
> Hi Kurt
>
> Yesterday here in the UK it reached 32 C in some parts of the south.
Well, yesterday we had 4" of rain here in the SW corner of Oz.
And the minimum temp in the state was -2C. Waaay up north, near
the WA/NT border (just a hop-step-and-jump from Indonesia and
only about 15 degrees south).
But still no real snow in the ozzie alps.
CD
=========================================================================
From: Simon Busbridge <S.C.Busbridge@bton.ac.uk>
Subject: [JN] FET/DHT Hybrid cascode
Date: Mon, 16 Oct 2000 09:07:57 +0100 (BST)
Source: Sound Digest Archive v02.n693
Hi All,
Thanks to everyone who responded to my Hovland question.
Having convinced myself that the fet/triode a la Alan Wright is way better
than any transformer I have ever heard, I was wondering if anyone has
tried using a DHT for the upper triode? Something like the DC70
subminature running from a 1.5 V battery.
My phono preamp is sounding good, with plenty of low level information
coming through, but it is perhaps a touch "smooth".
Also, has anyone tried the EC1000 for audio? This is another subminature
type, high g, low ra, with the grid connection coming out the other end to
the other connections.
Simon
Simon Busbridge, BSc(Hons) PhD CPhys MInstP
School of Engineering
University of Brighton
Lewes Road
Moulsecoomb
Brighton BN2 4GJ
UNITED KINGDOM
Tel: 0044 (0)1273 642542
Fax: 0044 (0)1273 642327/642301
e-mail: s.c.busbridge@bton.ac.uk, scbusbridge@hotmail.com
=========================================================================
From: Allen Wright <AllenVSE@compuserve.com>
Subject: [JN] FET Matching
Date: Fri, 30 Apr 1999 05:39:49 -0400
Source: Sound Digest Archive v02.n135
Guido wrote:
>>>Most FETs I match are done like:
>Tie source and gate together, conect to ground. Connect drain to 10 V
>(example)
>Measure current and make a note on a smaal sticker that can be attached to
>the FET<<<
This is fine to match them for IDSS, but perhaps not perfect if you intend
to run the fet at a current below this "max" level.
My trick matching machine allows one to set the current at which the match
is to be done - and then precisely measure the gate/source voltage needed
to give that current. FETs with a ~15mA IDSS who have the _same_
gate/source voltage at the choosen current (say 6.25mA) will be found to be
very well matched in circuit.
This matching alone can drop the 2nd harmonic distortion content down some
20dB over unmatched fets!
Allen (VSE)
=========================================================================
From: evaguido <EvaGuido@iaehv.nl>
Subject: [JN] FET Matching
Date: Fri, 30 Apr 1999 10:45:00 +0200
Source: Sound Digest Archive v02.n135
Most FETs I match are done like:
Tie source and gate together, conect to ground. Connect drain to 10 V
(example)
Measure current and make a note on a smaal sticker that can be attached to
the FET
Warming up of the FET makes current change a little, so watch the curent
and wait for stable reading
P-Fets shall be reverse connected !
Guido
=========================================================================
From: evaguido <EvaGuido@iaehv.nl>
Subject: Re: [JN] FET Matching
Date: Sat, 01 May 1999 14:34:44 +0200
Source: Sound Digest Archive v02.n135
Allen,
Thanks for extending the FET match
One step more could be to look at dynamic matching as well, but one needs
lots of FETs to find pairs then...
Guido
At 05:39 30/04/99 -0400, Allen Wright wrote:
>Guido wrote:
>
>>>>Most FETs I match are done like:
>
>>Tie source and gate together, conect to ground. Connect drain to 10 V
>>(example)
>
>>Measure current and make a note on a smaal sticker that can be attached to
>>the FET<<<
>
>This is fine to match them for IDSS, but perhaps not perfect if you intend
>to run the fet at a current below this "max" level.
>
>My trick matching machine allows one to set the current at which the match
>is to be done - and then precisely measure the gate/source voltage needed
>to give that current. FETs with a ~15mA IDSS who have the _same_
>gate/source voltage at the choosen current (say 6.25mA) will be found to be
>very well matched in circuit.
>
>This matching alone can drop the 2nd harmonic distortion content down some
>20dB over unmatched fets!
>
>Allen (VSE)
>
>
=========================================================================
From: "Michael (Mick)Maloney" <supra@cantech.net.au>
Subject: [JN] Fets
Date: Tue, 25 Jul 2000 06:00:17 +0800
Source: Sound Digest Archive v02.n609
I had to replace a fet on my SS active crossover. 24dB Link/phase aligned.
Looking at the circuit again I got a shock to see the design is now 13
years old, but I haven't come across anything that looks as good or comes
close to it's sound.
I only rarely touch SS and these chips have been in for quite a few years-
AD743 singles and AD712 duals- has anything come along recently that would
improve the sonics( not just specs).
Mick M
=========================================================================
From: "T. Loesch" <ezee_e@hotmail.com>
Subject: Re: [JN] Fets
Date: Tue, 25 Jul 2000 10:41:13 GMT
Source: Sound Digest Archive v02.n609
Hi,
>AD743 singles and AD712 duals- has anything come along recently that would
>improve the sonics( not just specs).
Yes. They are called valves.... ;-)
Without knowing the exact Circuit I cannot comment if the LM6172 and similar
as well as AD811 could be succesfully employed. But I'd say build a decent
Valve based X-Over.
Later T
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Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com
=========================================================================
From: "T. Loesch" <ezee_e@hotmail.com>
Subject: Re: [JN] Fets
Date: Tue, 25 Jul 2000 11:46:04 GMT
Source: Sound Digest Archive v02.n609
Mick,
>Not as easy as that- the active has phase alignment and time delay-
Nothing stops you from building that into a Valve X-Over....
I personally would think a simple transformeroutput "linestage", followed by
a set of a few kOhm Impedance level LC Crossover Filters which then are
followed by partially active time/phase alignment circuits. These Circuits
could be made also with Output Transformers, so probably 2 Valves per
Phase/Timealignment Circuit (and thus per channel) plus one (or an existing
transformercoupled Linestage) for the Input.
Surely that is at least philosophically better....
>-would much prefer valves if possible, but the implementation would be
>beyond most-SB could probably do it .
I'd do it quite easily too. I used to build active X-Overs for PA Purposes,
including such niceties as delays and continous variable phaseshift and CD
Horn EQ's using only discrete components and no conventional Op-Amp
Structures (differential amp, the SE Voltage Amp, then "Lin" Outputstage).
All filters where discrete Darlingtons as Followers on a Constant Current
Source. The variable All-Pass filters for the Delay where mostly passive
too....
This stuff sounded ton's better than anything we got our hands on untill we
went Digital with one of the early Yamaha Units. The problems of my units
was that they required plug in Modules to change the X-over Frequencies. The
Yamaha Digital sounded not much worse but was infinitly easier to adjust.
These Days I'd probably build around AD811's though. Difficult to apply, but
very good sounding. Only for Home I'd probably go passive linelevel LC
mostly and do the rest as simple as possible.
BTW, if you wind your own Inductors on Ferrite Pot Cores for the Linelevel
LCXO you can fit many taps and make the X-Over points switchable....
Later T
________________________________________________________________________
Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com
=========================================================================
From: "Michael (Mick)Maloney" <supra@cantech.net.au>
Subject: Re: [JN] Fets
Date: Tue, 25 Jul 2000 19:05:57 +0800
Source: Sound Digest Archive v02.n609
At 10:41 25/07/00 GMT, you wrote:
>Hi,
>
>>AD743 singles and AD712 duals- has anything come along recently that would
>>improve the sonics( not just specs).
>
>Yes. They are called valves.... ;-)
>
>Without knowing the exact Circuit I cannot comment if the LM6172 and similar
>as well as AD811 could be succesfully employed. But I'd say build a decent
>Valve based X-Over.
Not as easy as that- the active has phase alignment and time delay- I tried
a few valve actives that had same slopes, crossover points but the horns
sound like horns- the SS version makes them sing, image ,etc. Pisses me off
- -would much prefer valves if possible, but the implementation would be
beyond most-SB could probably do it .
MM
http://www.cantech.net.au/~supra/
SUPRATEK TRIODE " valve amplifiers for those who demand absolute sound and
finish-worldwide "
Mick Maloney
3 Parkside Ave Mt Pleasant Western Australia 6153
Ph/Fax 61 8 93644385 supra@cantech.net.au
=========================================================================
From: "Michael (Mick)Maloney" <supra@cantech.net.au>
Subject: Re: [JN] Fets
Date: Wed, 26 Jul 2000 07:49:49 +0800
Source: Sound Digest Archive v02.n609
At 11:46 25/07/00 GMT, you wrote:
>Mick,
>
>>Not as easy as that- the active has phase alignment and time delay-
>
>Nothing stops you from building that into a Valve X-Over....
>
>I personally would think a simple transformeroutput "linestage", followed by
>a set of a few kOhm Impedance level LC Crossover Filters which then are
>followed by partially active time/phase alignment circuits. These Circuits
>could be made also with Output Transformers, so probably 2 Valves per
>Phase/Timealignment Circuit (and thus per channel) plus one (or an existing
>transformercoupled Linestage) for the Input.
>
>Surely that is at least philosophically better....
For sure and your interpretation is very solid- I'm impressed.
MM
http://www.cantech.net.au/~supra/
SUPRATEK TRIODE " valve amplifiers for those who demand absolute sound and
finish-worldwide "
Mick Maloney
3 Parkside Ave Mt Pleasant Western Australia 6153
Ph/Fax 61 8 93644385 supra@cantech.net.au
=========================================================================
From: TubeGarden@aol.com
Subject: Re: [JN] Fets and fits
Date: Tue, 25 Jul 2000 07:49:57 EDT
Source: Sound Digest Archive v02.n609
In a message dated 7/25/00 4:12:53 AM US Mountain Standard Time,
supra@cantech.net.au writes:
> SUPRATEK TRIODE " valve amplifiers for those who demand absolute sound and
> finish-worldwide "
> Mick Maloney
Greets Mick,
Al's Pretty Good Tube Garden Variety Audio "for those who accept good sound
if it happens"
Happy Ears!
Al B^}
=========================================================================
From: "Norman Tracy" <ntracy@galstar.com>
Subject: RE: [JN] Fets - (Op's actually)
Date: Fri, 28 Jul 2000 22:45:50 -0500
Source: Sound Digest Archive v02.n612
Hi Mick,
Coming up for air and thought I'd reply to a couple of Joe-net postings
which have caught my eye over the last couple of weeks. I'm currently
focused on the PCB layout for the X-DAC 3.24 192k/24bit upgrade boards. It
is intense, but of course what I do for a break is, what else, sit at the
computer and type! :-/
First off my complements on your amazing craftsmanship as shown on:
http://www.cantech.net.au/~supra/
WOW ! ! ! !
On to your question, perhaps I can offer a suggestion beyond 'get thermonic'
(which when it was offered gave me a chuckle given your system). You asked:
> I only rarely touch SS and these chips have been in for quite a few years-
> AD743 singles and AD712 duals- has anything come along recently that would
> improve the sonics( not just specs).
A couple of suggestions. There is quite a buzz around the AD825 among those
of us who condescend to listen to the occasional bit of sand. Like my old
favorite AD811 it is damn fast (41MHz -3dB) and has a stout output stage (50
mA min). What is cool is these are combined with a JFET input stage with but
20 pA of input bias current and 12 nVrootHz of input voltage noise. One
challenge is its only available as a 8-pin SOIC. So to swap out your AD743
singles you would need a SOIC to DIP adapter such as those by Aries or
solder it to a 8-pin DIP component carrier. Its a single so an adapter would
be needed to use 2 ea. AD825 in place of each AD712 dual. Here the SOIC
package is a help to get it all to fit. These adapters to replace dual
op-amps with a pair of higher performance singles is an old CD upgrade
trick. I always thought the effort was worth it.
The second idea is more off the wall because here I am going to suggest a
part with but one amp per 16-pin DIP or SMD package. Perhaps it will be of
use if your x-over has input buffers.
As part of the X-DAC 3.24 R&D I tested three ways to do the differential to
single ended conversion needed by latest generation DAC chips.
- - 1. The AD SSM2017 audio diff-amp,
- - 2. using std. op-amps configured as diff-amps,
- - 3. the Burr-Brown INA103 instrumentation amp.
Adapters allowed each to be tried in turn in the prototype X-DAC 3.24. Each
was checked on the bench to confirm sanity but judgement as to which is best
was based on listening. Before comparisons various op-amps were tried in
DUT#2 and B-B OPA627AP was selected as the sweetest choice. Then listening
comparisons between options 1, 2, & 3 were run. When I got to the INA103 it
was one of those pick-your-jaw-up-off-de-floor moments. Everything about the
reproduction just opened up. Images were more dimensional, the highs
sweeter, and bass deeper AND better defined. Subtleties of instrumental
texture were better presented. Greater information retrieval (to borrow a
phrase from Linn) is the watchword. The improvement of 96/24 reproduction
over 44/16 was much greater as the INA103 let more of the extra information
through.
Now, this is obviously a radical suggestion as adapting to use INA103 in
place of regular single and dual op-amps is not trivial. I have not tried
using INAs in filter circuits, some serious design thought is needed here.
Also as in any op-amp swap project one has to keep the impedances around the
part (esp. input source Z) in mind. The INA103 wants a source Z of less then
10k ohms. For apps over that BB suggests their INA111 or INA114 (which I
have not tried). Typical thinking has limited INA103 to microphone pre-amps
and phono stages. Based on the results in my listening room I am spun up to
try it in other applications ASAP.
DISCLAIMER: Yes we can do X-DAC 3.24 analog stage with tubes or (my
preference) transformers & tubes. I research and design in solid state
because it is ever so much easier for a ACG customer to leave out a sand
state analog section in favor of tubes than to fit a AD811 into a 5842
socket!
happy listening
Norman Tracy
Audio Crafters Guild
5102 E 38 PL
Tulsa OK 74135 USA
918.627.5878 voice
918.481.0970 fax
ntracy@galstar.com e-mail
www.galstar.com/~ntracy/acg URL
=========================================================================
From: "Wolfgang Braun" <wb@braunbaustoffe.de>
Subject: Re: [JN] Fets - (Op's actually)
Date: Mon, 31 Jul 2000 11:09:25 +0200
Source: Sound Digest Archive v02.n614
Hi all,
after a baby break of two years i'm back in the net again.
Some words to my person:
I'm living in Germany and building tube amps for more than 15 years now.
Some of the project are mod of a Audio Res. SP 3, active 3way crossover,
2 own Pre with RIAA, EL 34 PP, PX4 SE and a PX 25 SE. My latest project is a
VV52 (completion 2001). Recently i replaced my Edgar/Klipsch Hornsystem
by an open baffle PHY-HP with a Klipsch corner horn as Sub and a Fostex T725
as tweeter.
I plan to go to Arhus´and hopefully i meet some of you (i didn't come into
contact to Kurt until now)
Wolfgang
Wolfgang Braun
wb@braunbaustoffe.de
=========================================================================
From: Patrick Currie <tubesguy@chorus.net>
Subject: [JN] FET sources?
Date: Sat, 8 May 1999 11:08:34 -0500 (CDT)
Source: Sound Digest Archive v02.n138
Hi all -
Can't seem to find the FETs that were mentioned last week in any of my
mailorder catalogs, including Allied, Mouser, and DigiKey. Does anyone
have any sources, matched or unmatched, cryoed or not? TIA - Pat
=========================================================================
From: "PEARL Cust Serv" <custserv@pearl-hifi.com>
Subject: Re: [JN] FFT / spectrum analyser
Date: Wed, 10 Mar 1999 10:48:50 -0700
Source: Sound Digest Archive v02.n070
Hi Guido:
Here's an excerpt from a mail I received from a friend who works for
- -hp- in test and measurement
- -------------------------------------
Bill -
Here is the link to software by HpW Works. The Lite version is
available for a 21 day day trial, after that costs $70. or so. You need to
download the "Lite" SW (1.54Mbyte) and then the "Sound Driver"(300kbyte),
run the exe files on both, and then have fun.
This is more than amateur software - this is very good stuff, and a 5
minute drive by whistling into my microphone showed me THD of my whistle
tone, with options to save THD data to clipboard, etc. - really nice SW
IMHO. Hats off to the designer.
http://ourworld.compuserve.com/homepages/hpwidmer/
- ------------------------------------
...and here's a question I sent to them, along with their reply:
>>> Hello,
>>> Which of the many sound cards do you recommend for 96/24 use?
Currently, I do not have any experiances with such cards......
while I deal with digital I/O cards and uses external
adc/dac evaluation boards.
While the adc/dac's chips's will improve over time and the base card
(digital I/O) will remain in the noisy (RF, EMI) PC. Now it seams that AKM
wins performance wise against crystal chips.
I/O cards who I used/use :
- - RME PCI digi 32 pro (old card without doublex)
- - RME PCI digi 96/8 pro with enhanced full doublex (record and play sample
rate may differenet)
see www.rme-audio.com
- - Adb18 pro ......who have a perfomance problem while they uses the ISA-Bus
and have low local buffer (REM has 128KBytes and supports up to 3 cards
using one shared IRQ)
Best Regards
HpW
E-Mail : HpWidmer@compuserve.com
==================================
. . .and to date that's what I know.
Bill Perkins, PEARL Inc.
2528 19 St. S.W., Calgary, Ab.,
Canada T2T 4X3
Ph. 1 403 244 4434 Fx. 1 403 244 9026
- ----------
>From: evaguido <EvaGuido@iaehv.nl>
> Hi all,
>
> I would like to use my PC with soundcar d as a spectrum analyser. I have
> been looking around for software and various programs have been found and
> tried, but not one satisfies.
>
> Anyone of you with experience and advises ?
>
> Guido
>
>
=========================================================================
From: Kalman Rubinson <kr4@is2.nyu.edu>
Subject: Re: [JN] FFT / spectrum analyser
Date: Wed, 10 Mar 1999 12:22:30 -0500 (EST)
Source: Sound Digest Archive v02.n070
On Wed, 10 Mar 1999, evaguido wrote:
> I would like to use my PC with soundcar d as a spectrum analyser. I have
> been looking around for software and various programs have been found and
> tried, but not one satisfies.
>
> Anyone of you with experience and advises ?
Spectra Plus
Kal
=========================================================================
From: evaguido <EvaGuido@iaehv.nl>
Subject: [JN] FFT / spectrum analyser
Date: Wed, 10 Mar 1999 14:52:57 +0100
Source: Sound Digest Archive v02.n070
Hi all,
I would like to use my PC with soundcar d as a spectrum analyser. I have
been looking around for software and various programs have been found and
tried, but not one satisfies.
Anyone of you with experience and advises ?
Guido
=========================================================================
From: Paul Joppa <pdj@ISDNseattle.net>
Subject: Re: [JN] FFT / spectrum analyser
Date: Wed, 10 Mar 1999 22:31:28 -0800
Source: Sound Digest Archive v02.n071
Second the motion. It's what our lab people at work like, too, and
they are pretty fussy.
- -Paul Joppa
p.s. it's a local company, too! :^)
Kalman Rubinson wrote:
>
> On Wed, 10 Mar 1999, evaguido wrote:
>
> > I would like to use my PC with soundcar d as a spectrum analyser. I have
> > been looking around for software and various programs have been found and
> > tried, but not one satisfies.
> >
> > Anyone of you with experience and advises ?
>
> Spectra Plus
>
> Kal
=========================================================================
From: "Lance Dow" <elldee@ldow.freeserve.co.uk>
Subject: Re: [JN] FFT / spectrum analyser
Date: Thu, 11 Mar 1999 21:38:34 -0000
Source: Sound Digest Archive v02.n071
Paul Joppa wrote;
> Second the motion. It's what our lab people at work like, too, and
> they are pretty fussy.
>
> -Paul Joppa
>
> p.s. it's a local company, too! :^)
According to the Web page (or the Readme file, can't remember
which), SpectraPlus is not available for sale outside the US. You can
download a 30-day evaluation copy but you can't buy it after if you
like it. What torture :-).
Lance
elldee@ldow.freeserve.co.uk
=========================================================================
From: trs@carlsmith.com
Subject: Re: [JN] FFT / spectrum analyser -Reply
Date: Wed, 10 Mar 1999 8:44:27 -1000
Source: Sound Digest Archive v02.n070
Dear Guido-
Right now I' checking out LabView from National Instruments,
along with one of their plug-in DAC cards. IT looks like it'll
take some lite programming and banging on the side of the
computer case to get it configured as an audio freq.
spectrum analyzer, but seems very flexible. Try
www.natinst.com if you're interested. Anyone else have any
experience with this software/hardware?How about you
digital wizards out there?
Regards, Tom Sylvester trs@carlsmith.com
>>> "kr4@is2.nyu.edu" 03/10/99 08:43am >>>
On Wed, 10 Mar 1999, evaguido wrote:
> I would like to use my PC with soundcar d as a spectrum
analyser. I have
> been looking around for software and various programs
have been found and
> tried, but not one satisfies.
>
> Anyone of you with experience and advises ?
=========================================================================
From: RALPH POWER <POWER.RALPH@epamail.epa.gov>
Subject: [JN] Fidelio cabinets for Lowthers
Date: Mon, 25 Jan 1999 16:11:58 -0500
Source: Sound Digest Archive v02.n012
Hi,
Can someone direct me to a source for plans, kits, or ready-built Fidelio
cabinets for Lowthers ?
Anyone have any narrow Lowther cabinets or kits for sale ?
TIA for info,
- Ralph
=========================================================================
From: David Tan <dtkky@singnet.com.sg>
Subject: Re: [JN] Fidelio cabinets for Lowthers
Date: Tue, 26 Jan 1999 09:01:29 +0800
Source: Sound Digest Archive v02.n012
Hi Ralph and all,
The Lowther site has them now and you can download all 6 gif files for free.
(www.lowtherloudspeakers.co.uk)
David Tan
RALPH POWER wrote:
> Hi,
>
> Can someone direct me to a source for plans, kits, or ready-built Fidelio
> cabinets for Lowthers ?
>
> Anyone have any narrow Lowther cabinets or kits for sale ?
>
> TIA for info,
>
> - Ralph
=========================================================================
From: "=?ISO-8859-1?Q?Torbj=F8rn_Lien?=" <mdrivekl@online.no>
Subject: [JN] Field-Coil magnets....
Date: Fri, 16 Jul 1999 15:02:24 +0200
Source: Sound Digest Archive v02.n206
Hello all.
This is far out,-anyway:
The last days I've been looking at the small
JBL 123A mag-system to check out the useability
for re-building it to a field coil, by changing
the alnico-puck and center poleplate with a part
made of soft-iron.
I did find that it is indeed possible,-if the
desired gap flux is not to be much higher than
the original 10OOO gauss....(This mag-system
seems very well designed from the start, no
surprice....)
I did some calculations with a voicecoil gap
made narrower,-(thinking the inner poleplate
diameter to be encreased),-so that the V.C.gap
could be decreased to 0,75mm. According to my
calculations, it should be possible to reach
saturation around the gap at approx. 2 Tesla ,
but then the ampereturns needed is 1200
for the airgap alone, and with an estimate of approx
800 A-turns for the rest of the magnet, a total of
2000 A-turns is required.....
Looking at a possible excite-coil, if made of 1mm
plain enammeled copper,approx 475 turns could be made
to fit inside the iron bell..This coil would be running
with 4,21 Amperes, and with a ohmic resistanse of approx. 2,75 ohms,-
12VDC would be needed.
This means the loss to be nearly 50W!!,-which is way to
much.........
(But if the voicecoil gap was *sealed* on the inside,-
with, say a flux-shorting ring,-then it would be possible
to drill two holes in the iron bell,-on opposite sides,
to let a heat transferring fluid circulate from magnet-guts to an
outside radiator.......)
Ohwell, it would still be a shitty design...
Anyone have beaten/blown 515 baskets's/mags for sale/trade?
A nice summer to all!
Regards
Torbjoern Lien, Norway
>
>
>
>
=========================================================================
From: Timo Christ <carnivor@uni-bremen.de>
Subject: [JN] field coil or hybrid magnet system
Date: Fri, 19 May 2000 16:26:49 +0200
Source: Sound Digest Archive v02.n552
Hi all driver designers out there,
a while ago, Torbjørn Lien implanted the idea to experiment with a
field coil in my "hungarian" midrange drivers.
Now i think this is interesting.
I would like to keep the original Alnico magnet and wind the coil around
it... if that has been tried and rejected, let me know.
The idea is to reinforce the permanent magnet field.
Alternatively the magnet could be replaced by a steel piece , although i
can't see at the moment why this would be necessary.
Anyway, it is impossible to say something without a little
visualization, so please see this URL:
http://www-user.uni-bremen.de/~carnivor/drivers/magnet.html
Every comment is welcome, especially from the speaker designer front.
I would like to try this, if it doesn't work out i could always use the
coil as a filter choke... :-)
Best Regards
Timo
- --
____
/ __ \ Timo Christ carnivore@uni-bremen.de
|....| EE Student University of Bremen, Germany
\_/\_/ Horns 'r more fun:
|||| http://www-user.uni-bremen.de/~carnivor/
=========================================================================
From: "=?ISO-8859-1?Q?Torbj=F8rn_Lien?=" <mdrivekl@online.no>
Subject: Re: [JN] field coil or hybrid magnet system
Date: Sat, 20 May 2000 04:09:55 +0200
Source: Sound Digest Archive v02.n552
Hello Timo, all....
>
> a while ago, Torbjørn Lien implanted the idea to experiment with a
> field coil in my "hungarian" midrange drivers.
> Now i think this is interesting.
> I would like to keep the original Alnico magnet and wind the coil around
> it... if that has been tried and rejected, let me know.
> The idea is to reinforce the permanent magnet field.
>
Wellllll....Unless you swap your alnico-magnets for some more or less equal
sized soft-iron pucks, it will not work. To make an electromagnet, you need
a core with good permeability and high flux-saturation limit...
I've written about this on afew occations in the past, but, having had
atleast
two disc-crashes in between I haven't any of the old notes. So this is by
memory and a bit unpresise:
Alnico will do no good as core, as the permeability is close to 1. While
good
iron has value around 4000-6000...
If you manage to swap the puck for some iron, internal space to house the
exciter-coil will probably become the next problem. I've found that few
drivers
have big enough magnet "internal cavity" to house it: Because driving
approx.
2 Tesla across an airgap of say 1mm takes h e a p s of ampereturns.
(I havent the formulas in head/at hand, but memory sez 2000+...
I once, as an excercise tried to determin the coil-requirements for
rebuilding
the modest-sized JBL 123A / LE10 magnet into an electromagnet. The coil
was supposed to drive the iron around airgap into saturation, resulting in
a flux-
density of 2 Tesla. I found it to be possible, on paper that is, but then
the copper
loss exceeded 60W!! Uhm,- n o t very friendly surroundings for the
voice-coil....
I remember that flux-density/copper-loss only started to look good at
levels
around 1 Tesla,- which BTW is the original working-point....
So I believe it's only possible to rebuild units to a higher flux-density
if they
are born overkill (oversized iron-path in the magnet-motor) to begin with.
It
would then be possible to rebuild an Altec-unit if the 515-type,-and the
big-pot JBL 1" compressiondriver.( LE85, 2470-20). I don't know of
others......
> Alternatively the magnet could be replaced by a steel piece , although i
> can't see at the moment why this would be necessary.
>
Above.....
>
> I would like to try this, if it doesn't work out i could always use the
> coil as a filter choke... :-)
>
:)With the speaker iron-parts as core? You wouldn't want to use t h a t
in your amp IMO...
> Best Regards
> Timo
HTH
Regards
Torbjoern
>
>
>
=========================================================================
From: Timo Christ <carnivor@uni-bremen.de>
Subject: Re: [JN] field coil or hybrid magnet system
Date: Sun, 21 May 2000 12:21:27 +0200
Source: Sound Digest Archive v02.n553
Hello Torbjørn, all
[Torbjørn wrote:]
> Wellllll....Unless you swap your alnico-magnets for some more or less
equal
> sized soft-iron pucks, it will not work. To make an electromagnet, you
need
> a core with good permeability and high flux-saturation limit...
> I've written about this on afew occations in the past, but, having had
> atleast
> two disc-crashes in between I haven't any of the old notes. So this is
by
> memory and a bit unpresise:
>
> Alnico will do no good as core, as the permeability is close to 1.
While
> good
> iron has value around 4000-6000...
well, ok. I can use the alnicos as refridgerator magnets. <g>
> If you manage to swap the puck for some iron, internal space to house
the
> exciter-coil will probably become the next problem. I've found that few
> drivers
> have big enough magnet "internal cavity" to house it: Because driving
> approx.
> 2 Tesla across an airgap of say 1mm takes h e a p s of ampereturns.
> (I havent the formulas in head/at hand, but memory sez 2000+...
Maximum dimensions of a field coil for this driver are:
Inner diameter 55 mm
Outer diameter 85 mm
Height 29 mm
(assuming size of the iron puck = alnico magnet size)
Gap width is 1mm.
Given the maximum dimensions, i think a coil of about 500g copper is
realistic.
What about 363 windings of 1mm copper wire, about 80 m = 500g.
That would be a resistance of about 1,9 Ohm.
To get 1563 ampereturns (per Finn Hammer's formula) we run 4,4 Ampere
through the coil.
Dissipation of the coil is now ca. 37 W.
IMHO this is reasonable. (?)
I will look for some wire. (Any cheap sources known?)
RS charges DM 20 for a 500g spool.
> I once, as an excercise tried to determin the coil-requirements for
> rebuilding
> the modest-sized JBL 123A / LE10 magnet into an electromagnet. The coil
> was supposed to drive the iron around airgap into saturation, resulting
in
> a flux-
> density of 2 Tesla. I found it to be possible, on paper that is, but
then
> the copper
> loss exceeded 60W!! Uhm,- n o t very friendly surroundings for the
> voice-coil....
>
> I remember that flux-density/copper-loss only started to look good at
> levels
> around 1 Tesla,- which BTW is the original working-point....
1 Tesla is already quite good, i think.
> So I believe it's only possible to rebuild units to a higher
flux-density
> if they
> are born overkill (oversized iron-path in the magnet-motor) to begin
with.
> It
> would then be possible to rebuild an Altec-unit if the 515-type,-and the
> big-pot JBL 1" compressiondriver.( LE85, 2470-20). I don't know of
> others......
my idea of using the coil as a filter choke if the experiment fails was
meant without iron - as air core in low voltage supplies.
It will be very interesting to see how the driver reacts at different
magnet strength levels. :-)
Regards
Timo
- --
____
/ __ \ Timo Christ carnivore@uni-bremen.de
|....| EE Student University of Bremen, Germany
\_/\_/ Horns 'r more fun:
|||| http://www-user.uni-bremen.de/~carnivor/
=========================================================================
From: "=?ISO-8859-1?Q?Torbj=F8rn_Lien?=" <mdrivekl@online.no>
Subject: Re: [JN] field coil or hybrid magnet system
Date: Sun, 21 May 2000 22:10:31 +0200
Source: Sound Digest Archive v02.n554
Hello Timo, all.
> Given the maximum dimensions, i think a coil of about 500g copper is
> realistic.
> What about 363 windings of 1mm copper wire, about 80 m = 500g.
> That would be a resistance of about 1,9 Ohm.
> To get 1563 ampereturns (per Finn Hammer's formula) we run 4,4 Ampere
> through the coil.
> Dissipation of the coil is now ca. 37 W.
> IMHO this is reasonable. (?)
IMO it's too much,-. Unless convection cooled, your voicecoil will be
severe heated via the centre-pole. Then it's resistance would take to drift
upwards...
The fieldcoil speakers/horndrivers I've played with have all had a
coil-loss around 10-15W.
> >
> > I remember that flux-density/copper-loss only started to look good at
> > levels > > around 1 Tesla,- which BTW is the original working-point....
>
> 1 Tesla is already quite good, i think.
>
:) Well,-it depends on what you want to accomplish by rebuilding
your driver. The above comment was to indicate that there seems to be no
free flux-density (lunch),- Meaning that an alnico-system of a given size
is not likely to be much boosted flux-vice, if at all, by the exchanging of
the
perm. magnet to a field coil magnet. Unless the magnet-system is made with
a generous inner space for the coil. But,-although not boosted, the
encreased
stiffness of the new magnet-field might still be desireable.
>
> my idea of using the coil as a filter choke if the experiment fails was
> meant without iron - as air core in low voltage supplies.
>
Now that is different...
>
> It will be very interesting to see how the driver reacts at different
> magnet strength levels. :-)
>
I have tried this, but very brief. (On some theatre-drivers without horns.)
Impression was that the sound, except for sheer volume changed very
little,-
if at all....Yes, puzzling, isn't it,- I would have guessed that at lower
flux-densities
the sound would start to mellow,-but it didn't. I also tried overpowering
the
coils with up to tripple the power. No audible change, compared to the
idling point set by the manufacturer..(This was my last, hasty experiment
in
our old appartment before moving,-so conclusion might just aswell change
under more relaxed circumstances..)
Regards
Torbjoern, Norway
=========================================================================
From: =?iso-8859-1?Q?Pierre-Fr=E9d=E9ric_Caillaud?= <pfcaillaud@cryptalis.com>
Subject: [JN] Re: FIFO and DAC
Date: Wed, 6 Jun 2001 11:16:07 +0200
Source: Sound Digest Archive v02.n901
C'est un message de format MIME en plusieurs parties.
- ------=_NextPart_000_0299_01C0EE7A.15767740
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charset="iso-8859-1"
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DAC Project :
The idea on this is to avoid making a PLL and a VCXO. I know Guido's =
PLL is world record, I would never want (nor could) attempt to redesign =
it.
The clock (XO) will be in the Dac. Maybe 2 cm. from the chip itself. =
All we need is a divider to get it to the right frequency, and a latch. =
All this inside a shielded metal box with its own power supply.
The PLL problem is sidestepped. But we have to feed the clock to the =
transport now. There will be 2 links then : clock (DAC to transport via =
fiber), and data :
Steal the I2S signal coming to the CD63 Digital filter, take it (via =
optical fiber) to a DF1704/PCM1704 located outboard. DF1704 will be =
bypassable to get a 0-Oversampling DAC. I like the slow rolloff filter =
too, in the 1704.
Questions here to the specialists :
- What do you think about this idea ?
- Layout : I will use point to point wiring (deadbug). Can this be =
as good as a good 4-layer PCB ? The advantage of PTP is that I can use =
twisted pairs and shortest paths.
- On frequency : what frequency shall I use and shall I have to =
select a transport that has the same XO frequency as the 1704 ? Can =
somebody brief me on this ?
- ---------------------------------------------
On FIFOs and Jitter : Discman anti-shock memory could be used as a =
FIFO ?
Andrew gives a very useful bit of info below. This sounds very =
perverted but absolutely not unlikely !=20
Thanks for the tip, I'll check.
My discman is a Panasonic actually. As stand-alone it doesn't sound =
that good, but would you expect something that runs on 3V to be able to =
drive 300 ohms headphones ?...
I guess I'll rather rip open the CD-63SE another time then. Or, =
maybe buy a cheapo brand new CD player for that sole purpose : =
suggestions on brands and models, anyone ?
Actually the size of the buffer that is needed is rather small. =
Something like 1 bit I may say. This means, no buffer, just a latch. =
Something to account for the propagation delay from the DAC to the =
transport and back.
Suggestions, anyone ?
Pierre
----- Original Message -----=20
From: Andrew Andrew=20
To: tnt-audioaddicts@yahoogroups.com=20
Sent: Wednesday, June 06, 2001 8:55 AM
Subject: [tntaudioaddicts] FIFO in discman.
Hi Pierre-Fr=E9d=E9ric Caillaud
Just a short note that may save you some wasted time. The CD player I =
worked=20
on at Philips which had shock memory used a really filthy delta =
compresion=20
technique. On the basis that if you were jogging with in ear crappy=20
headphones it was unlikely you would be able to hear the difference. =
This=20
extended the storage time significantly for a given size of memory and =
so=20
saved money.
It is likely that Sony have used a similar scheme in your walk man. If =
you=20
want to be sure open the player find the memory chip look it up on the =
web=20
and see how many 16 bit samples could be stored in it. If this doesn't =
tally=20
with the time stated for the shock memory then it must be using =
compresion=20
and I would bet its not anything good.
Andy.D
- ------=_NextPart_000_0299_01C0EE7A.15767740
Content-Type: text/html;
charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML><HEAD>
<META content=3D"text/html; charset=3Diso-8859-1" =
http-equiv=3DContent-Type>
<META content=3D"MSHTML 5.00.3103.1000" name=3DGENERATOR>
<STYLE></STYLE>
</HEAD>
<BODY bgColor=3D#ffffff><FONT face=3DArial size=3D2>
<DIV><FONT face=3DArial size=3D2> DAC Project =
:</FONT></DIV>
<DIV> </DIV><FONT face=3DArial size=3D2>
<DIV><FONT face=3DArial size=3D2> The idea on this is =
to avoid=20
making a PLL and a VCXO. I know Guido's PLL is world record, I would =
never want=20
(nor could) attempt to redesign it.</FONT></DIV>
<DIV> </DIV>
<DIV>
<DIV><FONT face=3DArial size=3D2> The clock (XO) will =
be in the=20
Dac. Maybe 2 cm. from the chip itself. All we need is a divider to get =
it to the=20
right frequency, and a latch. All this inside a shielded metal box with =
its own=20
power supply.</FONT></DIV>
<DIV><FONT face=3DArial size=3D2> The PLL problem =
is=20
sidestepped. But we have to feed the clock to the transport now. =
There will=20
be 2 links then : clock (DAC to transport via fiber), and data =
:</FONT></DIV>
<DIV> </DIV></DIV>
<DIV> Steal the I2S signal coming to the CD63 Digital =
filter,=20
take it (via optical fiber) to a DF1704/PCM1704 located outboard. DF1704 =
will be=20
bypassable to get a 0-Oversampling DAC. I like the slow rolloff filter =
too, in=20
the 1704.</FONT></DIV>
<DIV> </DIV>
<DIV> Questions here to the specialists :</DIV>
<DIV> - What do you think about this idea ?</DIV>
<DIV> - Layout : I will use point to point wiring =
(deadbug).=20
Can this be as good as a good 4-layer PCB ? The advantage of PTP is that =
I can=20
use twisted pairs and shortest paths.</DIV>
<DIV> </DIV>
<DIV> - On frequency : what frequency shall I use and =
shall I=20
have to select a transport that has the same XO frequency as the 1704 ? =
Can=20
somebody brief me on this ?</DIV>
<DIV> </DIV>
<DIV>---------------------------------------------</DIV>
<DIV> </DIV>
<DIV> On FIFOs and Jitter : Discman anti-shock memory =
could be=20
used as a FIFO ?</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=3DArial size=3D2> Andrew gives a very =
useful bit=20
of info below. This sounds very perverted but absolutely not =
unlikely !=20
</FONT></DIV>
<DIV><FONT face=3DArial size=3D2> Thanks for the tip, =
I'll=20
check.</FONT></DIV>
<DIV><FONT face=3DArial size=3D2> My discman is a =
Panasonic=20
actually. As stand-alone it doesn't sound that good, but would you =
expect=20
something that runs on 3V to be able to drive 300 ohms headphones=20
?...</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=3DArial size=3D2> I guess I'll rather =
rip open the=20
CD-63SE another time then. Or, maybe buy a cheapo brand new CD player =
for that=20
sole purpose : suggestions on brands and models, anyone ?</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=3DArial size=3D2> Actually the size of =
the buffer=20
that is needed is rather small. Something like 1 bit I may say. This =
means, no=20
buffer, just a latch. Something to account for the propagation delay =
from the=20
DAC to the transport and back.</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=3DArial size=3D2> Suggestions, anyone=20
?</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=3DArial size=3D2> Pierre</FONT></DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV> </DIV>
<BLOCKQUOTE=20
style=3D"BORDER-LEFT: #000000 2px solid; MARGIN-LEFT: 5px; MARGIN-RIGHT: =
0px; PADDING-LEFT: 5px; PADDING-RIGHT: 0px">
<DIV style=3D"FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV=20
style=3D"BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: =
black"><B>From:</B>=20
<A href=3D"mailto:gfiandy@hotmail.com" =
title=3Dgfiandy@hotmail.com>Andrew=20
Andrew</A> </DIV>
<DIV style=3D"FONT: 10pt arial"><B>To:</B> <A=20
href=3D"mailto:tnt-audioaddicts@yahoogroups.com"=20
=
title=3Dtnt-audioaddicts@yahoogroups.com>tnt-audioaddicts@yahoogroups.com=
</A>=20
</DIV>
<DIV style=3D"FONT: 10pt arial"><B>Sent:</B> Wednesday, June 06, 2001 =
8:55=20
AM</DIV>
<DIV style=3D"FONT: 10pt arial"><B>Subject:</B> [tntaudioaddicts] FIFO =
in=20
discman.</DIV>
<DIV><BR></DIV>Hi Pierre-Fr=E9d=E9ric Caillaud<BR><BR>Just a short =
note that may=20
save you some wasted time. The CD player I worked <BR>on at Philips =
which had=20
shock memory used a really filthy delta compresion <BR>technique. On =
the basis=20
that if you were jogging with in ear crappy <BR>headphones it was =
unlikely you=20
would be able to hear the difference. This <BR>extended the storage =
time=20
significantly for a given size of memory and so <BR>saved money.<BR>It =
is=20
likely that Sony have used a similar scheme in your walk man. If you =
<BR>want=20
to be sure open the player find the memory chip look it up on the web =
<BR>and=20
see how many 16 bit samples could be stored in it. If this doesn't =
tally=20
<BR>with the time stated for the shock memory then it must be using =
compresion=20
<BR>and I would bet its not anything=20
good.<BR><BR>Andy.D<BR><BR></BLOCKQUOTE></BODY></HTML>
- ------=_NextPart_000_0299_01C0EE7A.15767740--
=========================================================================
From: "Michael Cameron" <mncameron@worldnet.att.net>
Subject: [JN] Filament Chokes
Date: Mon, 20 Sep 1999 20:18:55 -0700
Source: Sound Digest Archive v02.n282
Hello Joes
Does anyone on the list use filament chokes in their amps? If so what
benefits do you get from using them?
Thanks
michael
=========================================================================
From: MHuber@t-online.de (Manfred Huber)
Subject: [JN] Filament CS
Date: Thu, 18 Feb 1999 08:49:37 +0100
Source: Sound Digest Archive v02.n048
- --_=_=_=IMA.BOUNDARY.F7CB2P138764=_=_=_
Content-Type: text/plain; charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable
Joes,
I generally find current regulated DHT filaments better sounding than
voltage regulated ones. I don=B4t konow why this is so. Perhaps
someone can comment.
I have built a simple 1A filament current regulator for my 6A3 amp
that performs really good. I=B4d like to share it with you.
Manfred
- ------------------
Manfred Huber
MHuber@t-online.de
- ------------------
- --_=_=_=IMA.BOUNDARY.F7CB2P138764=_=_=_
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- --_=_=_=IMA.BOUNDARY.F7CB2P138764=_=_=_--
=========================================================================
From: MHuber@t-online.de (Manfred Huber)
Subject: [JN] Re: Filament CS
Date: Thu, 18 Feb 1999 08:54:47 +0100
Source: Sound Digest Archive v02.n048
Joes,
please note that source and drain of the NDP6020P are mixed up
in my schematic. Rats.
Manfred
- ------------------
Manfred Huber
MHuber@t-online.de
- ------------------
=========================================================================
From: Torsten.Loesch@enhar-ha.nthames.nhs.uk
Subject: Re: [JN] Filament CS
Date: 18 Feb 1999 11:04:15 +0000
Source: Sound Digest Archive v02.n049
Hi there,
> I generally find current regulated DHT filaments better sounding than
> voltage regulated ones. I don´t konow why this is so. Perhaps
> someone can comment.
Well, here is my personal take. A Current-source (even the most rudimentary one using a LM317 reg) h
as a relatively high Output impedance when compared to a voltage regulator.
I forgot what the LM317 CCS clocks in, but a few Kilo-ohm at least. If the same thing is used as Vol
tage Regulator the output Impedance is a few dozend milliohm.
So, making the assumtion that the Filament is not entierly unaffected by teh signal and hence will c
hange it's current-draw somewhat with changing signal (now where did I read that?), the Transient (A
C) behaviour of the Regulator will sneak through.
One of our London Live DIY-Circle members SWEARS he hears the difference between a FET "Zenner-follo
wer" and a 317 (as Voltage reg) on Filaments and prefers the "zero-feedback" reg (I think that was b
lind-tested even...).
Now a current-source has such a (realtively) high output Impedance when compared to the heater in th
e Valve (about 4.2 Ohm for a 300B), that whatever transient and other nasties sneak through will be
severely attenuated.
I'm sure that are are further processes happening that have to do with (if memory serves) cathode Co
oloing (?) by the current-flow and so on.
Later Thorsten
=========================================================================
From: RALPH POWER <POWER.RALPH@epamail.epa.gov>
Subject: [JN] Filament supply for the SJS MC phono stage
Date: Wed, 16 Jun 1999 09:53:24 -0400
Source: Sound Digest Archive v02.n180
Hi All,
BTW, I've really enjoyed all the "Darling" excitement recently. A simple and
inexpensive DIY amp that gives real listening pleasure is what this hobby is all
about IMHO.
Bob you ARE the man !
I've been real busy with lately with a big email conversion at work and with the
kids out of school for summer and have neglected debugging my SJS MC
phono stage project. It's is virtually complete, but I'm just stuck and can't
seem to get any further without some help.
My question is regarding the regulated filament supply for the phono stage
and I hope someone can help point me to the problem. The schematic I'm
using is for the filament supply is the same as for the SJS MM phono stage at:
http://www.users.globalnet.co.uk/~valveamp/images/PH102.GIF
OK, here's the deal : When I measure the filament voltage to the tube sockets
without the preamp tubes in, I measure ~ 6.2 volts DC, but when I put the tubes in,
I measure NO voltage at all at the sockets ! B+ seems OK.
I'm using one filament supply per channel and should be well within the current
rating of the LM317T regulator. Also I'm using a trimpot on the ADJ leg of the
regulator so I can trim the voltage precisely. Other than that, I've attempted to
duplicate the schematic precisely. This is only the second regulated filament
supply I've built and never one quite this complicated.
Any suggestions or advice much appreciated.
Thanks in advance,
- Ralph
=========================================================================
From: Allen Wright <AllenVSE@compuserve.com>
Subject: [JN] Filament supply for the SJS MC phono stage
Date: Wed, 16 Jun 1999 18:36:32 -0400
Source: Sound Digest Archive v02.n180
Ralph asked:
>>>OK, here's the deal : When I measure the filament voltage
to the tube sockets without the preamp tubes in, I measure ~ 6.2 volts DC,
but when I put the tubes in, I measure NO voltage at all at the sockets !
B+ seems OK<<
If it is really built per the SJS map it should work fine - just as long
as:
1/ The 317 itself is OK - they can be wierd little geeks!
2/ It is heatsinked adequately - you are using a metal TO-3 or
metal/plastic TO-220 version - yes?
3/ The inrush current of the tubes isn't hitting it's current limit and
shutting it down. When not using current sourced heaters I like to use a
series resistor in line with the tube (say 6.8 ohms) and feed the
combination with a litle more voltage. Much easier on the tubes across
time.
>>I'm using one filament supply per channel and should be well within the
current
rating of the LM317T regulator<<<
Should be.
>>> Also I'm using a trimpot on the ADJ leg of the
regulator so I can trim the voltage precisely<<<
Do you have the trimpot from output to adjust, or from adjust to gnd? It
should be the second option...
They're my best shots.
Allen (VSE)
=========================================================================
From: Christian Rintelen <rintelen@datacomm.ch>
Subject: Re: [JN] Filament supply for the SJS MC phono stage
Date: Wed, 16 Jun 1999 20:33:33 +0200
Source: Sound Digest Archive v02.n180
- --------------CF7DA77D4FBBFCF85AE388E5
Content-Type: text/plain; charset=us-ascii; x-mac-type="54455854"; x-mac-creator="4D4F5353"
Content-Transfer-Encoding: 7bit
Ralph,
the fil supply is more or less the off the mill type. I've built several like these.
There are a few things that can go wrong and IMO improved.
1. Check out the pin-out of the reg. With the tab at the rear, it's (left to right)
adjust - out - in and not as drawn in - adj - out
2. Check out the direction of the diode across the reg: the arrow must go to the left
- -- if mounted the other way around, you bypass the reg...
3. (Not on the drawing): Insert a 0.1 ohm 4W resistor between the rectifier bridge and
the first cap and a 1 or 2 ohm / 4W resistor between the two 470 uF caps -- this will
smooth out ripple and limit the voltage drop the reg has to handle (less heat, less
stress...)
4. For further protection of the reg add a diode in series between the 220 uF and the
22 uF cap with the arrow pointing to the right
5. Remove the 22 ohm resistor across the reg
6. What value does the trim pot have? (Should be between 1 and 5k; I'm using a 240 ohm
resistor [instead of 150] between out and adj and a 5 k trimpot for my 6.3 V regulated
filament supply)
7. Is the reg properly heat sinked?
8. How much voltage can you regulate with the trim pot w/o tubes?
9. Try substituting the tube with a 20 ohm / 4 W resistor (or more) to see if the reg
works under load. If so:
> OK, here's the deal : When I measure the filament voltage to the tube sockets
> without the preamp tubes in, I measure ~ 6.2 volts DC, but when I put the tubes in,
> I measure NO voltage at all at the sockets !
10. This sounds like a short. Stupid question: Are you sure you got the heater voltage
connected to the right socket pins (pins 3 and 9)? If you measure w/o tubes and then
put the tubes in: Does the reg get hot?
11. If this doesn't help: recheck everything and have it rechecked by somebody else
12. Good luck...
Christian
- --------------CF7DA77D4FBBFCF85AE388E5
Content-Type: text/html; charset=us-ascii
Content-Transfer-Encoding: 7bit
<!doctype html public "-//w3c//dtd html 4.0 transitional//en">
<html>
Ralph,
<br>the fil supply is more or less the off the mill type. I've built several
like these. There are a few things that can go wrong and IMO improved.
<p>1. Check out the pin-out of the reg. With the tab at the rear, it's
(left to right) adjust - out - in and not as drawn in - adj - out
<br>2. Check out the direction of the diode across the reg: the arrow must
go to the left -- if mounted the other way around, you bypass the reg...
<br>3. (Not on the drawing): Insert a 0.1 ohm 4W resistor between the rectifier
bridge and the first cap and a 1 or 2 ohm / 4W resistor between the two
470 uF caps -- this will smooth out ripple and limit the voltage drop the
reg has to handle (less heat, less stress...)
<br>4. For further protection of the reg add a diode in series between
the 220 uF and the 22 uF cap with the arrow pointing to the right
<br>5. Remove the 22 ohm resistor across the reg
<br>6. What value does the trim pot have? (Should be between 1 and 5k;
I'm using a 240 ohm resistor [instead of 150] between out and adj and a
5 k trimpot for my 6.3 V regulated filament supply)
<br>7. Is the reg properly heat sinked?
<br>8. How much voltage can you regulate with the trim pot w/o tubes?
<br>9. Try substituting the tube with a 20 ohm / 4 W resistor (or more)
to see if the reg works under load. If so:
<blockquote TYPE=CITE>OK, here's the deal : When I measure the filament
voltage to the tube sockets
<br>without the preamp tubes in, I measure ~ 6.2 volts DC, but when I put
the tubes in,
<br>I measure NO voltage at all at the sockets !</blockquote>
10. This sounds like a short. Stupid question: Are you sure you got the
heater voltage connected to the right socket pins (pins 3 and 9)? If you
measure w/o tubes and then put the tubes in: Does the reg get hot?
<br>11. If this doesn't help: recheck everything and have it rechecked
by somebody else
<br>12. Good luck...
<p>Christian</html>
- --------------CF7DA77D4FBBFCF85AE388E5--
=========================================================================
From: RALPH POWER <POWER.RALPH@epamail.epa.gov>
Subject: [JN] Re: Filament supply for the SJS MC phono stage
Date: Thu, 24 Jun 1999 13:07:44 -0400
Source: Sound Digest Archive v02.n187
Hi ,
Much thanks to Larry, John, Andrej, Christian, Allen, and Daniel for all the helpful
pointers regarding my misbehaving filament supply.
As my carelessness would have it, it was a "small oversight" on my part in
neglecting to install a jumper between terminal strips to continue the
output of the voltage regulator. It was trying to pass it all through the
1N4002 diode.
The filament voltages are fine now, so now I'm checking out plate voltages on
the 417As and the 6922s and sorting out my grounding scheme and hum levels.
I now have a new Denon DL-103 to use with this preamp, all I have to do is
mount it up. This preamp has so much gain, I'm a little afraid of hooking
it up to my system !
Thanks for the help,
- Ralph
=========================================================================
From: Roscoe Primrose <roscoe@aiko.com>
Subject: [JN] Filament voltage vs. current?
Date: Wed, 13 Jun 2001 20:30:46 -0400
Source: Sound Digest Archive v02.n909
With regulated DC filaments, what's more important, the rated current or
the rated voltage?
Peace
- --
Roscoe Primrose
- -- mailto:roscoe@aiko.com -- http://www.aiko.com/roscoe --
"Once in a while you get shown the light
In the strangest of places if you look at it right." Robert Hunter
=========================================================================
From: evaguido <EvaGuido@iaehv.nl>
Subject: Re: [JN] Filament voltage vs. current?
Date: Thu, 14 Jun 2001 22:19:39 +0200
Source: Sound Digest Archive v02.n910
Hi Roscoe
In the end the cathode temperature is important, so the average power
counts, I tend to say.....
Guido
At 20:30 13-6-01 -0400, Roscoe Primrose wrote:
>With regulated DC filaments, what's more important, the rated current or
>the rated voltage?
>
>Peace
>--
>Roscoe Primrose
>-- mailto:roscoe@aiko.com -- http://www.aiko.com/roscoe --
>
>"Once in a while you get shown the light
>In the strangest of places if you look at it right." Robert Hunter
=========================================================================
From: "PEARL Cust Serv" <custserv@pearl-hifi.com>
Subject: [JN] Re: File Attachments
Date: Thu, 19 Aug 1999 12:29:15 +0000
Source: Sound Digest Archive v02.n255
Hi Jeremy:
Well, it's nice know that I did something wrt sending attachments RIGHT
for a change.
That photo was just a garden-variety .jpg, generated in Photoshop 3.0.5
PPC Version (for the Mac). I sent it thru Outlook Express 4.5 using UUEncode
encoding.
Bill Perkins,
PEARL, Inc.
Unit 200, 2137 33rd Ave. S.W.,
Calgary, Ab.,
Canada T2T 1Z7
Ph. 1 403 244 4434 Fx. 1 403 244 9026
- ----------
>From: Jeremy Epstein <jepstein@shwd.com>
>To: Joenet <sound@lists.io.com>, custserv@pearl-hifi.com
>Subject: File Attachments
>Date: Thu, Aug 19, 1999, 6:30 PM
>
> I subscribe to the JoeNet digest. With the exception of Bill's 6550
> photo yesterday, every graphic file attachment I've ever seen sent to
> JoeNet has looked like this:
>
> D2tzszu/+HPUwxadcs4lR1vwprfu+/bav45dZ7x7n8lZ18ky/XWYr2W60uI9B15t
> 2ps/bHbLWde98dRzV/7y1qEf3mHoo1/9+RnjJh9545XjgAmazUt//ZTVP4nlmYaC
>
> In other words, gibberish text.
>
> 1) What did you do differently, Bill?
>
> 2) Do the subscribers to the "streaming" JoeNet see these file
> attachments (like Bob D's of today) OK? What about other digest
> subscribers?
>
> -j
> --
> =====================================
> Jeremy Epstein .... jepstein@shwd.com
> =====================================
=========================================================================
From: William Eckle <wmeckle@uswest.net>
Subject: Re: [JN] File Attachments
Date: Thu, 19 Aug 1999 14:25:51 -0700
Source: Sound Digest Archive v02.n255
At 02:30 PM 8/19/99 -0400, Jeremy Epstein wrote:
>I subscribe to the JoeNet digest. With the exception of Bill's 6550
>photo yesterday, every graphic file attachment I've ever seen sent to
>JoeNet has looked like this:
>
>D2tzszu/+HPUwxadcs4lR1vwprfu+/bav45dZ7x7n8lZ18ky/XWYr2W60uI9B15t
>2ps/bHbLWde98dRzV/7y1qEf3mHoo1/9+RnjJh9545XjgAmazUt//ZTVP4nlmYaC
>
>In other words, gibberish text.
Hi Jeremy:
I see you are using Netscape 3.0, it will read GIFs & JPGs, but you'll have to add other reader
s to the plug ins (helpers) in Netscape 3.0.. If you get a PDF extension, point a plug in for PDF to
read where you have your Adobe PDF reader (acrord32.exe) for 32 bit version 4.0 Acrobat. If it has
a BMP extension, point your plug in to where paint.exe resides, and on and on for any other pix you
receive.
Netscape will read all if you point it to the reader for that particular extension.
The easiest thing to do is have all attachments directed to a special directory you create (I u
se BUF for buffer),
I then can read them, and move those I want to save to a directory for that catagory.
Hope this helps.
<bold><color><param>ffff,0000,0000</param>-=Bill Eckle=-
</color></bold>wmeckle@uswest.net
<italic><color><param>0000,0000,ffff</param>Phoenix, Arizona
USA</color></italic>
=========================================================================
From: Jeremy Epstein <jepstein@shwd.com>
Subject: [JN] File Attachments
Date: Thu, 19 Aug 1999 14:30:58 -0400
Source: Sound Digest Archive v02.n255
I subscribe to the JoeNet digest. With the exception of Bill's 6550
photo yesterday, every graphic file attachment I've ever seen sent to
JoeNet has looked like this:
D2tzszu/+HPUwxadcs4lR1vwprfu+/bav45dZ7x7n8lZ18ky/XWYr2W60uI9B15t
2ps/bHbLWde98dRzV/7y1qEf3mHoo1/9+RnjJh9545XjgAmazUt//ZTVP4nlmYaC
In other words, gibberish text.
1) What did you do differently, Bill?
2) Do the subscribers to the "streaming" JoeNet see these file
attachments (like Bob D's of today) OK? What about other digest
subscribers?
- -j
- --
=====================================
Jeremy Epstein .... jepstein@shwd.com
=====================================
=========================================================================
From: davidbarnett@aristotle.net (David Barnett)
Subject: Re: [JN] File Attachments
Date: Thu, 19 Aug 1999 21:27:55 GMT
Source: Sound Digest Archive v02.n255
On Thu, 19 Aug 1999 14:30:58 -0400, Jeremy Epstein <jepstein@shwd.com>
wrote:
>2) Do the subscribers to the "streaming" JoeNet see these file
>attachments (like Bob D's of today) OK?
Yes.
- --dnb
=========================================================================
From: "Johari Yip" <hfyip@pacific.net.sg>
Subject: Re: [JN] File Attachments
Date: Fri, 20 Aug 1999 08:29:19 +0800
Source: Sound Digest Archive v02.n255
Hey, I have the same problem and I'm using IE5. What's going on?
Johari
- ----- Original Message -----
From: Jeremy Epstein <jepstein@shwd.com>
To: Joenet <sound@lists.io.com>; <custserv@pearl-hifi.com>
Sent: Friday, August 20, 1999 2:30 AM
Subject: [JN] File Attachments
> I subscribe to the JoeNet digest. With the exception of Bill's 6550
> photo yesterday, every graphic file attachment I've ever seen sent to
> JoeNet has looked like this:
>
> D2tzszu/+HPUwxadcs4lR1vwprfu+/bav45dZ7x7n8lZ18ky/XWYr2W60uI9B15t
> 2ps/bHbLWde98dRzV/7y1qEf3mHoo1/9+RnjJh9545XjgAmazUt//ZTVP4nlmYaC
>
> In other words, gibberish text.
>
> 1) What did you do differently, Bill?
>
> 2) Do the subscribers to the "streaming" JoeNet see these file
> attachments (like Bob D's of today) OK? What about other digest
> subscribers?
>
> -j
> --
> =====================================
> Jeremy Epstein .... jepstein@shwd.com
> =====================================
=========================================================================
From: Jeremy Epstein <jepstein@shwd.com>
Subject: Re: [JN] File Attachments
Date: Fri, 20 Aug 1999 08:46:52 -0400
Source: Sound Digest Archive v02.n256
William Eckle wrote:
> Hi Jeremy:
> I see you are using Netscape 3.0, it will read GIFs & JPGs, but you'll
> have to add other readers to the plug ins (helpers) in Netscape 3.0..
Bill, Thanks you for the help BUT : I am on a network where plug-ins
have been disabled. So far I have a helper app for PDF's but I rely on
Netscape to read jpg's and gif's. However, that's really all I'm looking
for.
My suspicion is that the encoding (BASE64) used on the digest is messing
me up somehow; I get inline gif's and jpg's OK from other sources.
BTW, here's a tip for those of you who have to set up helper apps (at
least in UNIX this works) : add %s to the command you use to call the
helper app and the app will open with the linked file displaying in its
window. I just managed to learn this yesterday. (For example, "acroread
%s" opens Acrobat reader for me, displaying the file whose link I just
clicked on. Without the %s, it just opened Acrobat with a blank window,
and worse, then I'd have to go back and explicitly download and save the
PDF, and then open it from Acrobat from my hard drive. Big drag.)
Thanks Bill!
- -j
- --
=====================================
Jeremy Epstein .... jepstein@shwd.com
=====================================
=========================================================================
From: Tim Reese <tgrmail@nmr.MGH.harvard.EDU>
Subject: Re: [JN] File Attachments
Date: Sun, 22 Aug 1999 13:34:42 -0400 (EDT)
Source: Sound Digest Archive v02.n260
>William Eckle wrote:
>
>> Hi Jeremy:
>> I see you are using Netscape 3.0, it will read GIFs & JPGs, but you'll
>> have to add other readers to the plug ins (helpers) in Netscape 3.0..
>
>Bill, Thanks you for the help BUT : I am on a network where plug-ins
>have been disabled. So far I have a helper app for PDF's but I rely on
>Netscape to read jpg's and gif's. However, that's really all I'm looking
>for.
>
>My suspicion is that the encoding (BASE64) used on the digest is messing
>me up somehow; I get inline gif's and jpg's OK from other sources.
>
>BTW, here's a tip for those of you who have to set up helper apps (at
>least in UNIX this works) : add %s to the command you use to call the
>helper app and the app will open with the linked file displaying in its
>window. I just managed to learn this yesterday. (For example, "acroread
>%s" opens Acrobat reader for me, displaying the file whose link I just
>clicked on. Without the %s, it just opened Acrobat with a blank window,
>and worse, then I'd have to go back and explicitly download and save the
>PDF, and then open it from Acrobat from my hard drive. Big drag.)
Thanks for the tip JE
>
>Thanks Bill!
>
>-j
>--
>=====================================
>Jeremy Epstein .... jepstein@shwd.com
>=====================================
>
Blasted BASE64 stuff! Seems like an unneeded binary conversion standard
invented to make PC apps incompatible with the rest of the world. I can
easily handle URLs or uuencoded graphics, but I have yet to get BASE64 files
to display independently from mail (ie from xv or some other UNIXy display
program via a conversion program to TIFF, GIF, .rs, whatever). Probably
some goofy uSoft "extension" that's gumming up the works.
One possibility is to run Eudora and send your mail to a Mac or PC, where
your browser can handle it.
I would prefer no enclosures, plain text, and URLs for graphics. There are
plenty of joes that will host images if the poster has no web site.
Can you put up your DC phono stage as a URL Bob?
cheers & HTH tr
- ----------------------------------------------------------------------
Tim Reese, MGH NMR Center reese@nmr.MGH.harvard.edu
=========================================================================
From: William Eckle <wmeckle@uswest.net>
Subject: Re: [JN] Filed?
Date: Wed, 05 Jan 2000 03:37:44 -0700
Source: Sound Digest Archive v02.n386
At 08:23 AM 01/05/2000 +0100, Le Cleac'h J.-M. wrote:
>Dear Joenetters,
>
>Here is a file of the age and location for 72 Joenetters.
>The file was established on 2000 January 4, 6PM GMT
Looks like I'm due for the geezer award in this group !
<bold><color><param>ffff,0000,0000</param>-=Bill Eckle=-
</color></bold> wmeckle@uswest.net
<italic><color><param>0000,0000,ffff</param>Phoenix, Arizona USA
</color></italic>
=========================================================================
From: "Le Cleac'h J.-M." <lecleach@cgi.ensmp.fr>
Subject: [JN] Filed?
Date: Wed, 5 Jan 2000 08:23:19 +0100
Source: Sound Digest Archive v02.n386
Dear Joenetters,
Here is a file of the age and location for 72 Joenetters.
The file was established on 2000 January 4, 6PM GMT
Please, check if data that concern you is correct or not.
Best regards,
Jean-Michel Le Cleac'h, Paris, France
***********************************************************************
Aigner Josef 34 Vienna Austria
Arduman Adnan 46 Istanbul Turkey
Bailey David 34 Sudbury Ontario Canada
Barnett David 43 Little Rock Arkansas USA
Beck Chris 30 West Bend Wisconsin USA
Bergsson Kjartan 39 Reykjavik Iceland
Blank Rick 47 San Antonio Texas USA
Bohnen Aaron 27 Vancouver BC Canada
Bora Dragos-Silviu 30 Bacau Romania
Brennan Tom 51 Chicago USA
Brook Cameron 38 Perth West. Aus. Australia
Butterfield Paul 54 Winter Park Florida USA
Carr Jonathan 39 Setagaya-ku Tokyo Japan
Clark Peter 51 Scottsdale Arizona USA
Crittle David 35 Wagga Wagga Australia
Danley Tom 48 Chicago USA
Dean Hugh R. 49 Melbourne Australia
Doppenberg Bert 41 Nunspeet Netherlands
Dow Lance 48 London England UK
Eckle Bill 72 Phoenix Arizona USA
Edenholm Anders 47 London England UK
Fontana Vince 55 Philadelphy PA USA
Ganti Sridhar 33 Alameda California USA
Gardner Grover 43 Mt. Rainier MD USA
Gates Sam 47 Kilgore TX USA
Gaw Bill 53 Kensington New Hampshire USA
Giguere Sylvain 44 Quebec Canada
Graetke Robert 30 Bremerhaven Germany
Greene Michael 44 Long Island NY USA
Hardesty Dennis 47 Long Beach California USA
Hendricks Carter 48 St. Louis Missouri USA
Hopkins Ray 55 Rolla Missouri USA
Iwakura Mario Renato 35 Porto Alegre Brazil
Karlin Michael 50 Long Island NY USA
Kaufman Gary 40 Waban Massachussett USA
Kiskis Mindaugas 24 Vilnius Lithuania
Kubala Miroslav 44 Bern Switzerland
Lahlum Rodd J. 47 Mt.Prospect Chicago USA
Lawrence David 40 Hong Kong China
Le Cleac'h Jean-Michel 45 Paris France
Lewis Steve 46 Maui Hawaii USA
Loesch Thorsten 33 London England UK
Ma Tung-Cheung 36 Hong Kong China
Mackris Thom 49 Denver Colorado USA
Mak Alfia 40 Hong Kong China
Maloney Mick 47 West. Aus. Australia
Miglioranza Ritchie 33 Sudbury Ontario Canada
Mills Mark 45 Sommerset New Jersey USA
Mitaru Alex 50 Portland Oregon USA
Nixon Scott 48 High Point North Carolina USA
Pao Sammy 29 Los Angeles California USA
Perkins Bill 49 Calgary AB Canada
Pitoyo 35 Singapore Singapore
Pledger Joe Silverton Oregon USA
Power Ralph 46 Danielsville Georgia USA
Rintelen Christian 42 Zurich Switzerland
Ryan Dave 34 Minneapolis MN USA
Shamsul Bahrin Kamarudin 31 Sabah Malaysia
Sieg Phil 51 Knoxville Tennessee USA
Sikking Peter 30 Amsterdam Netherlands
Sl. Steven 29 Atlanta Ga USA
Smith Wendell 45 Kanehoe Hawaii USA
Snoeren Cuno 32 Netherlands
Tan David 37 Singapore Singapore
Taylor Dave 43 Boulder Colorado USA
Tent Guido 32 Eindhoven Netherlands
Thatcher R. 25 Cleveland Ohio USA
Torisawa Yuichi 42 Tokyo Japan
Ungemach Bob 48 Elm Grove Wisconsin USA
Volz Fred 34 State College Pennsylvania USA
Yip Johari 40 Yishun Singapore
Young Owen 49 New Zealand
Zyxtan Paul 33 Louisville Kentucky USA
***************************************************************************
=========================================================================
From: David Barnett <davidbarnett@aristotle.net>
Subject: Re: [JN] Filed?
Date: Wed, 05 Jan 2000 14:10:14 -0600
Source: Sound Digest Archive v02.n387
On Wed, 05 Jan 2000 03:37:44 -0700, William Eckle <wmeckle@uswest.net>
wrote:
> Looks like I'm due for the geezer award in this group !
Hey, don't worry, you're only as old as you look...
- --dnb
=========================================================================
From: "Phil Sieg" <psieg@nxs.net>
Subject: [JN] filler for tone arm tube.
Date: Sat, 15 May 1999 17:52:17 -0400
Source: Sound Digest Archive v02.n143
Joes,
I am in the process of rewiring an SME 3012R. The arm tube uses balsa wood
as a damping agent. Has anyone tried the spray insulating foam that
electricians use to fill in conduit running from exterior to interior to
replace something like the balsa wood in an arm tube? Any reason not to
try it? TIA.
Phil
=========================================================================
From: "David B. Klein" <dklein@microtec.net>
Subject: Re: [JN] filler for tone arm tube.
Date: Sat, 15 May 1999 18:53:56
Source: Sound Digest Archive v02.n143
A 12:31 AM 5/16/99 +0200, Hartmut Quaschik a écrit :
Same coldness is to be
>found in the Fidelity Research tonearms, BTW.
>
I have an FR-64S arm and don't find it cold, particularly, but I'm much
more interested these days in Bach, and whether the interpretation I'm
listening to conforms to my ideas of the music, so perhaps I'm not tuned in
on the 'right' level. Especially when the sound is coming from the CD
player :-) When I do use it, I use an FR silver transformer and MC 201
cartridge, by the way.
David
=========================================================================
From: Hartmut Quaschik <Hartmut.Quaschik@munich.netsurf.de>
Subject: Re: [JN] filler for tone arm tube.
Date: Sun, 16 May 1999 00:31:04 +0200
Source: Sound Digest Archive v02.n143
Phil,
the 3012R has a steel tube as opposed to the 3012II which has an aluminium
tube,
and the you can hear the steel ringing when not damped, this is critical.
Even with the balsa wood inside the 3012R sounds cold and frigid. The old
version 3012II is respected much better from sound, it is in fact more musical,
and nowadays is even more expensive second hand. Same coldness is to be
found in the Fidelity Research tonearms, BTW.
A friend of mine used loose wood fibres or cork particles for the 3012II, which
normally is undamped, but he did not report on what it did on the sound.
regards,
Hartmut from Munich - SME3012 afficionado
Phil Sieg schrieb:
> Joes,
>
> I am in the process of rewiring an SME 3012R. The arm tube uses balsa wood
> as a damping agent. Has anyone tried the spray insulating foam that
> electricians use to fill in conduit running from exterior to interior to
> replace something like the balsa wood in an arm tube? Any reason not to
> try it? TIA.
>
> Phil
=========================================================================
From: "Phil Sieg" <psieg@nxs.net>
Subject: Re: [JN] filler for tone arm tube.
Date: Sat, 15 May 1999 19:54:03 -0400
Source: Sound Digest Archive v02.n144
Hartmut,
I recognize that the 3013R has a steel tube and needs to be damped. What do
you think of insulating foam (the type you spray into a cavity and wait ~20
min. to harden) in place of the balsa wood? I agree the balsa's inadequate.
My question is can the foam be a better choice or is there yet something
even better and preferable? Thanks.
Best,
Phil
- ----- Original Message -----
From: Hartmut Quaschik <Hartmut.Quaschik@munich.netsurf.de>
To: Phil Sieg <psieg@nxs.net>; sound practice list
<sound@deliverator.io.com>
Sent: 15 May, 1999 18.31
Subject: Re: [JN] filler for tone arm tube.
> Phil,
>
> the 3012R has a steel tube as opposed to the 3012II which has an aluminium
> tube,
> and the you can hear the steel ringing when not damped, this is critical.
> Even with the balsa wood inside the 3012R sounds cold and frigid. The old
> version 3012II is respected much better from sound, it is in fact more
musical,
>
> and nowadays is even more expensive second hand. Same coldness is to be
> found in the Fidelity Research tonearms, BTW.
>
> A friend of mine used loose wood fibres or cork particles for the 3012II,
which
>
> normally is undamped, but he did not report on what it did on the sound.
>
> regards,
> Hartmut from Munich - SME3012 afficionado
>
> Phil Sieg schrieb:
>
> > Joes,
> >
> > I am in the process of rewiring an SME 3012R. The arm tube uses balsa
wood
> > as a damping agent. Has anyone tried the spray insulating foam that
> > electricians use to fill in conduit running from exterior to interior to
> > replace something like the balsa wood in an arm tube? Any reason not
to
> > try it? TIA.
> >
> > Phil
>
>
>
=========================================================================
From: davidbarnett@aristotle.net (David Barnett)
Subject: Re: [JN] filler for tone arm tube.
Date: Sun, 16 May 1999 01:15:16 GMT
Source: Sound Digest Archive v02.n144
On Sat, 15 May 1999 19:54:03 -0400, "Phil Sieg" <psieg@nxs.net>
wrote:
>My question is can the foam be a better choice or is there yet something
>even better and preferable?
Have you tried a piece of regular polyolefin heat-shrink tubing on the
outside of the tonearm? This would be in addition to the balsa
inside...
- --dnb
=========================================================================
From: Allen Wright <AllenVSE@compuserve.com>
Subject: [JN] filler for tone arm tube.
Date: Sun, 16 May 1999 07:30:11 -0400
Source: Sound Digest Archive v02.n144
Phil asked:
>>>Has anyone tried the spray insulating foam that
> electricians use to fill in conduit running from exterior to interior to
> replace something like the balsa wood in an arm tube? Any reason not to
> try it?
Could be awful hard to get it out again if you don't like it...
I would suggest trying a small thin ring of lead wound tight around the arm
out maybe 1/3 distance from the pivot. Moved to taste. This is not my idea,
I once had it demonstrated by a Japanese Physics Professor (who also
happened to own the SAEC tone arm company) that you need a _more_ dense and
_lower_ Q material to really damp hiQ resonances - and stainless steel
being both dense and hiQ needs something like lead. A less dense material
is of little effect in comparison - in my experience.
You would need a surprisingly small amount of lead to kill the SS's
resonances.
You could also try C37 - it could be the biggest positive surprise of
all...
Allen (VSE)
=========================================================================
From: "Phil Sieg" <psieg@nxs.net>
Subject: Re: [JN] filler for tone arm tube.
Date: Sun, 16 May 1999 08:56:46 -0400
Source: Sound Digest Archive v02.n144
Allen,
Do you use the lead ring or C37 in combo with the balsa stuffing or in place
of?
Phil
- ----- Original Message -----
From: Allen Wright <AllenVSE@compuserve.com>
To: JoeNet A <sound@lists.io.com>
Sent: 16 May, 1999 07.30
Subject: [JN] filler for tone arm tube.
> Phil asked:
>
> >>>Has anyone tried the spray insulating foam that
> > electricians use to fill in conduit running from exterior to interior to
> > replace something like the balsa wood in an arm tube? Any reason not
to
> > try it?
>
> Could be awful hard to get it out again if you don't like it...
>
> I would suggest trying a small thin ring of lead wound tight around the
arm
> out maybe 1/3 distance from the pivot. Moved to taste. This is not my
idea,
> I once had it demonstrated by a Japanese Physics Professor (who also
> happened to own the SAEC tone arm company) that you need a _more_ dense
and
> _lower_ Q material to really damp hiQ resonances - and stainless steel
> being both dense and hiQ needs something like lead. A less dense material
> is of little effect in comparison - in my experience.
>
> You would need a surprisingly small amount of lead to kill the SS's
> resonances.
>
> You could also try C37 - it could be the biggest positive surprise of
> all...
>
> Allen (VSE)
=========================================================================
From: Allen Wright <AllenVSE@compuserve.com>
Subject: Re: [JN] filler for tone arm tube.
Date: Mon, 17 May 1999 05:59:58 -0400
Source: Sound Digest Archive v02.n144
Phil asked:
>>>Do you use the lead ring or C37 in combo with the balsa stuffing or in
place
of?<<<
I would leave the damping the arm already has, as it is, and add the lead
extra.
Remember - if some's good and more's better - then too much should be about
right!
Allen (VSE)
=========================================================================
From: Thomas Danley <Tom@ppci.com>
Subject: Re: [JN] filler for tone arm tube.
Date: Mon, 17 May 1999 07:58:40 -0500
Source: Sound Digest Archive v02.n145
Phil Sieg wrote:
> Joes,
>
> I am in the process of rewiring an SME 3012R. The arm tube uses balsa wood
> as a damping agent. Has anyone tried the spray insulating foam that
> electricians use to fill in conduit running from exterior to interior to
> replace something like the balsa wood in an arm tube? Any reason not to
> try it? TIA.
>
> Phil
Hi
Since it is desirable to have a low moment of inertia, it is likely that
"filling" the tube with anything heavy would be a mistake (so far as
tracking). Remember that the natural frequency if too high will effect the
bass performance and if too low will effect tracking. If it were me, and my
SME are (which is "S" shaped), I would cut a strip of thin aluminum (like is
used as roof flashing) wide enough to just slip inside the tube and about 1/3
the length. of the tube
Get some actual damping liquid like is used on edge suspensions of loudspeakers
(like ws1291 from C.P. Moyen)
Then twist the aluminum into a spiral shape and insert it into the pivot end of
the arm. after putting some damping in the tube with a Q tip etc.
The idea is that the alum strip will ba "attached" to the tube with a VERY
lossy material, the strip which forms a constrained layer sort of and because
of the twist is absorptive in every direction and the high degree of damping
even damps the tube out near the cartridge end (where the alum strip is not).
Although the idea of balsa wood being used in an audio application may sound
very low tech, it turns out wood, in particular balsa wood has very good
acoustical properties. I have experimented with it as loudspeaker radiators
where the idea is (usually) to make something which is non resonant and has no
"preferred" frequencies and yet is as light and stiff as possible. (notice wood
pulp as in paper is still the most common radiator material). It turns out
wood has a superior property called "Euler buckling" (sp?).
It would be possible to have "preferred resonances" which coincide with musical
notes, this while possibly pleasing would be coloration which you certainly do
not want (should you play recording with "other" sounds). The idea is after all
to be able to re-produce any sound, harmonically related or not.
Best Regards,
Tom Danley
ServoDrive inc / Sound Physics Labs
=========================================================================
From: Christian Rintelen <rintelen@datacomm.ch>
Subject: Re: [JN] filler for tone arm tube.
Date: Mon, 17 May 1999 16:05:43 +0200
Source: Sound Digest Archive v02.n145
Thomas Danley wrote:
> Since it is desirable to have a low moment of inertia, it is likely that
> "filling" the tube with anything heavy would be a mistake (so far as
> tracking). Remember that the natural frequency if too high will effect the
> bass performance and if too low will effect tracking. If it were me, and my
> SME are (which is "S" shaped), I would cut a strip of thin aluminum (like is
> used as roof flashing) wide enough to just slip inside the tube and about 1/3
> the length. of the tube
We're talking about dynamic mass here. The two factors are weight and distance
from the pivot point. The distance is squared i.e. it makes a HUGE difference
wether the same weight is applied right at the pivot point or at the front end of
the headshell. Putting some lead around the arm tube near the pivot will not
effect the tracking greatly and it will also not "load" the cartridge too much.
This (and not the -- marginally -- reduced tracking error) IMHO is also the "real"
benefit of 12" tonearms over 9" arms. An Ortofon SPU for instance sounds more
dynamic on a 12" arm than on a 9" arm with the same tracking force. But we've been
thru this...
Christian
=========================================================================
From: Nicholas McKinney <nick@lambdacoustics.com>
Subject: [JN] Filter needed
Date: Fri, 26 Nov 1999 19:00:12 -0500
Source: Sound Digest Archive v02.n346
Hi Joes,
I am working on a project that needs what should be a simple filter for many of
you gurus.
I need to attenuate the response from 500hz to 10Khz by 3~6dB
Doing this directly at the speaker "sucks" I am finding.
However if done before a gain stage of a preamp, it would solve some other
problems as well.
So theoretically say we use a 6922, 6DJ8, 6N1P or similar in a typical voltage
gain stage.
There must be quite a few different ways of doing this that people are
opinioned on, with many different compromises as the result.
Engineering after all is an art of compromise.
Something else I have learned, ask questions of those that know more than you.
Which is why I am here, this is for a tube amp speaker after all.
Which means I need for this filter to work in a tube amp ;-)
TIA
Nick
Nicholas McKinney
Lambda Acoustics Inc.
www.lambdacoustics.com
www.onelist.com/community/LambdaDrivers
=========================================================================
From: "Graham Ingle." <blackcat.e@virgin.net>
Subject: [JN] Filters
Date: Thu, 11 Nov 1999 11:58:46 -0000
Source: Sound Digest Archive v02.n330
Gentlemen,
Can someone please tell me what is a "Crestran Filter Reactor"?
There is a 7.5H, 2.5H, 13.5H and a 6.5H in each can.
Thanks,
Graham.
blackcat electronics
blackcat.e@virgin.net
01253 855294 UK
=========================================================================
From: Rick Francis <rfrancis@glasscity.net>
Subject: Re: [JN] Filters
Date: Thu, 11 Nov 1999 15:23:49 -0500
Source: Sound Digest Archive v02.n330
Graham Ingle. wrote:
>
> Gentlemen,
>
> Can someone please tell me what is a "Crestran Filter Reactor"?
> There is a 7.5H, 2.5H, 13.5H and a 6.5H in each can.
>
For reasons I have yet to discover, during the WWII era, filter
chokes/inductors are often marked as "filter reactors." I used to have
some, marked thusly, that featured two chokes in a single container. I
left them with Doc Bottlehead in exchange for beer and parts, I think...
Looks like you found something more peculiar -- four separate chokes in
one can! You should be able to build some fancy power supplies with
those!
Rick
=========================================================================
From: russ arbuthnot <russ3@southern.com>
Subject: Re: [JN] filters - help
Date: Thu, 8 Feb 2001 11:15:50 -0600
Source: Sound Digest Archive v02.n801
On Thu, 8 Feb 2001, Simon Busbridge wrote:
> Phas is 45 deg (with appropriate sign) when wRC=1
sorry, what does 'w' equal to in the above statement?
thanks,
russ
=========================================================================
From: =?iso-8859-1?Q?Bj=F8rn_Aaholm?= <bjorn@vt52.com>
Subject: [JN] filters - help
Date: Thu, 8 Feb 2001 16:04:40 +0100
Source: Sound Digest Archive v02.n801
Hello Joes.
I'm one of the Joes that has learned everything I know about electronics
hands-on. I have no relevent education so my knowledge is full of holes :)
That's why I have to ask a few somewhat basic questions (I think).
What happens to the phase of the signal when it passes a simple high pass
filter such as an RC coupling in an amp?
Any difference if this is made as a lowpass filter?
What if two or more such filter stages are cascaded in order to get a
steeper slope?
Any difference if this is in a passive x-over in a speaker (other than a
series R will cause too high losses)?
Any other relevant info on the subject will be appreciated as well.
Thanks,
Bjørn Aaholm
=========================================================================
From: Simon Busbridge <S.C.Busbridge@bton.ac.uk>
Subject: Re: [JN] filters - help
Date: Thu, 8 Feb 2001 16:41:24 +0000 (GMT)
Source: Sound Digest Archive v02.n801
LPF phase = 0 when frequency = 0, phase -> -90 deg when phase -> infinity
HPF phase = 0 when frequency -> infinity, phase -> +90 deg when
frequency=0
Phas is 45 deg (with appropriate sign) when wRC=1
With cascaded filters it depends how they interact. If there is a buffer
between them then add phases and gains in dB
I hope this is the info you want.
Simon
Simon Busbridge, BSc(Hons) PhD CPhys MInstP
School of Engineering
University of Brighton
Lewes Road
Moulsecoomb
Brighton BN2 4GJ
UNITED KINGDOM
Tel: 0044 (0)1273 642542
Fax: 0044 (0)1273 642327/642301
e-mail: s.c.busbridge@bton.ac.uk, scbusbridge@hotmail.com
On Thu, 8 Feb 2001, [iso-8859-1] Bjørn Aaholm wrote:
> Hello Joes.
>
> I'm one of the Joes that has learned everything I know about electronics
> hands-on. I have no relevent education so my knowledge is full of holes :)
>
> That's why I have to ask a few somewhat basic questions (I think).
>
> What happens to the phase of the signal when it passes a simple high pass
> filter such as an RC coupling in an amp?
>
> Any difference if this is made as a lowpass filter?
>
> What if two or more such filter stages are cascaded in order to get a
> steeper slope?
>
> Any difference if this is in a passive x-over in a speaker (other than a
> series R will cause too high losses)?
>
> Any other relevant info on the subject will be appreciated as well.
>
> Thanks,
> Bjørn Aaholm
>
>
=========================================================================
From: "Chris Vryonides" <chrisvryonides@hotmail.com>
Subject: Re: [JN] filters - help
Date: Thu, 08 Feb 2001 17:15:29 -0000
Source: Sound Digest Archive v02.n801
Big can of worms there Bjorn!
See if you can get hold of a simulator like Electronics Workbench or spice
etc. Then you can see how all your inductively coupled tube stages will
interact (don't forget your Miller capacitances etc). As Simon says,
cascading stages is tricky to calc, unless there is a buffer between each
one.
Note also that a phase which is linear with frequency should not be too
audible (as it amounts to the same thing as a time delay).
How's your complex number maths, btw? If you're comfortable with this, I'll
explain how you can use it to calculate this stuff.
regards
Chris
>From: Simon Busbridge <S.C.Busbridge@bton.ac.uk>
>To: Bjørn Aaholm <bjorn@vt52.com>
>CC: Joe-Net <sound@lists.io.com>
>Subject: Re: [JN] filters - help
>Date: Thu, 8 Feb 2001 16:41:24 +0000 (GMT)
>
>LPF phase = 0 when frequency = 0, phase -> -90 deg when phase -> infinity
>HPF phase = 0 when frequency -> infinity, phase -> +90 deg when
>frequency=0
>
>Phas is 45 deg (with appropriate sign) when wRC=1
>
>With cascaded filters it depends how they interact. If there is a buffer
>between them then add phases and gains in dB
>
>I hope this is the info you want.
>
>Simon
>
>Simon Busbridge, BSc(Hons) PhD CPhys MInstP
>School of Engineering
>University of Brighton
>Lewes Road
>Moulsecoomb
>Brighton BN2 4GJ
>UNITED KINGDOM
>
>Tel: 0044 (0)1273 642542
>Fax: 0044 (0)1273 642327/642301
>e-mail: s.c.busbridge@bton.ac.uk, scbusbridge@hotmail.com
>
>
>On Thu, 8 Feb 2001, [iso-8859-1] Bjørn Aaholm wrote:
>
> > Hello Joes.
> >
> > I'm one of the Joes that has learned everything I know about electronics
> > hands-on. I have no relevent education so my knowledge is full of holes
>:)
> >
> > That's why I have to ask a few somewhat basic questions (I think).
> >
> > What happens to the phase of the signal when it passes a simple high
>pass
> > filter such as an RC coupling in an amp?
> >
> > Any difference if this is made as a lowpass filter?
> >
> > What if two or more such filter stages are cascaded in order to get a
> > steeper slope?
> >
> > Any difference if this is in a passive x-over in a speaker (other than a
> > series R will cause too high losses)?
> >
> > Any other relevant info on the subject will be appreciated as well.
> >
> > Thanks,
> > Bjørn Aaholm
> >
> >
>
>
_________________________________________________________________________
Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com.
=========================================================================
From: Simon Busbridge <S.C.Busbridge@bton.ac.uk>
Subject: Re: [JN] filters - help
Date: Thu, 8 Feb 2001 17:23:30 +0000 (GMT)
Source: Sound Digest Archive v02.n801
w = small "omega", the angular frequency. w = 2 * pi * f, where f is the
actual frequency in Hz.
w is measured in radians per second.
Simon
Simon Busbridge, BSc(Hons) PhD CPhys MInstP
School of Engineering
University of Brighton
Lewes Road
Moulsecoomb
Brighton BN2 4GJ
UNITED KINGDOM
Tel: 0044 (0)1273 642542
Fax: 0044 (0)1273 642327/642301
e-mail: s.c.busbridge@bton.ac.uk, scbusbridge@hotmail.com
On Thu, 8 Feb 2001, russ arbuthnot wrote:
>
>
>
> On Thu, 8 Feb 2001, Simon Busbridge wrote:
>
>
> > Phas is 45 deg (with appropriate sign) when wRC=1
>
> sorry, what does 'w' equal to in the above statement?
>
> thanks,
> russ
>
>
=========================================================================
From: "PEARL Cust. Service" <custserv@pearl-hifi.com>
Subject: Re: [JN] Filth
Date: Wed, 11 Apr 2001 12:18:52 -0700
Source: Sound Digest Archive v02.n864
Hello Raphael:
Not to point any sort of a finger, but I'm the only Joe I'm aware
of who makes transformers commercially and I assure you that I
am *not* responsible for your spam problems.
In fact, I have two other e-mail boxes that have become essentially
unusable due to *%^&^&%(*^ spammers. . . . and that is not to mention the
dedicated fax line that has likewise become a spammer's "portal"
Bill Perkins - PEARL, Inc.
> Yesterday my post box was spammed with many many
> pornography. We all know which
> transformer maker and his friends on Joenet
> do it. My children also use the same mailbox.
>
> Nothing remains to be said.
>
> Rafael Antonio Ferenghetti
=========================================================================
From: raf@SAFe-mail.net
Subject: [JN] Filth
Date: Wed, 11 Apr 2001 13:26:50 -0400
Source: Sound Digest Archive v02.n864
Yesterday my post box was spammed with many many
pornography. We all know which
transformer maker and his friends on Joenet
do it. My children also use the same mailbox.
Nothing remains to be said.
Rafael Antonio Ferenghetti
=========================================================================
From: "Phil Sieg" <psieg@nxs.net>
Subject: Re: [JN] Filth
Date: Wed, 11 Apr 2001 14:11:32 -0400
Source: Sound Digest Archive v02.n864
Take this somewhere else. This kind of crap ruined RAT, it's not wanted
here. I could care less about ego wars between Mike LeFevre and Andre Jute
or anyone else.
Mike makes transformers. I use and like his transformer. I don't care what
he does with the rest of his life as long as I get the transformers I want.
Andre Jute has provided me nothing of use in my exercise of this hobby.
Phil
- ----- Original Message -----
From: <raf@SAFe-mail.net>
To: <sound@io.com>
Sent: Wednesday, 11 April, 2001 13.26
Subject: [JN] Filth
> Yesterday my post box was spammed with many many
> pornography. We all know which
> transformer maker and his friends on Joenet
> do it. My children also use the same mailbox.
>
> Nothing remains to be said.
>
> Rafael Antonio Ferenghetti
>
=========================================================================
From: "BobC" <bobcx@nyc.rr.com>
Subject: Re: [JN] Filth
Date: Thu, 12 Apr 2001 18:21:05 -0400
Source: Sound Digest Archive v02.n864
- ----- Original Message -----
From: "PEARL Cust. Service" <custserv@pearl-hifi.com>
To: <sound@lists.io.com>
Sent: Wednesday, April 11, 2001 3:18 PM
Subject: Re: [JN] Filth
> Hello Raphael:
> Not to point any sort of a finger, but I'm the only Joe I'm aware
> of who makes transformers commercially and I assure you that I
> am *not* responsible for your spam problems.
Bill please don't waste your time as this is pure fiction posted by (Henry
A. Pasternack) = (RAF) who just wants to cause trouble here because he is
lonely.
regards
BC
> In fact, I have two other e-mail boxes that have become essentially
> unusable due to *%^&^&%(*^ spammers. . . . and that is not to mention the
> dedicated fax line that has likewise become a spammer's "portal"
>
>
> Bill Perkins - PEARL, Inc.
>
>
>
> > Yesterday my post box was spammed with many many
> > pornography. We all know which
> > transformer maker and his friends on Joenet
> > do it. My children also use the same mailbox.
> >
> > Nothing remains to be said.
> >
> > Rafael Antonio Ferenghetti
>
=========================================================================
From: Remco Stoutjesdijk <remco@ultranalog.com>
Subject: Re: [JN] Filth
Date: Thu, 12 Apr 2001 01:00:42 +0200
Source: Sound Digest Archive v02.n865
o------------------o
| |
| DON'T FEED |
| THE TROLLS |
| |
o------------------o
| |
| |
| |
| |
__ \|__|/__
Remco
- --
http://www.ultranalog.com
=========================================================================
From: raf@SAFe-mail.net
Subject: Re: [JN] Filth
Date: Fri, 13 Apr 2001 13:33:37 -0400
Source: Sound Digest Archive v02.n866
"BobC" <bobcx@nyc.rr.com> wrote:
>>>>posted by (Henry A. Pasternack) = (RAF) who
just wants to cause trouble here because he is
lonely.<<<<<
Thank you, Bob. Here is additional information sent
by the pornography makers about who requested
that pornography be sent to me:
>>>on 11:25:27 2001 PST
>>>>somebody is pretending to be you. Use the
following information to identify the person. They
connected from IP: 129.37.197.63 They used this
browser: Mozilla/4.75 [en] (Win98; U)<<<<<
IP: 129.37.197.63 is registered to
IBM Corporation
RT 100
Somers, NY 10589
US
Hundreds of people saw the same homosexual filth
posted to the Single Driver Conference. This was at the
time that those who stalk Andre disrupted
that list also with other posts from Henry
Pasternack, Michael LaFevre and
Bob Chernofsky.
That was bad, but pornography to children is very
very sick.
People who defend and tolerate such scum are also
trash.
Bill, I am sorry you get involved. Nobody think you
do it. Everybody know who is behind this evil
thing. Even his friend Phil Sieg name Mike LaFevre
of Magnequest Transformers. Now BobC name the member of
Mike's gang as Henry Pasternack. Maybe that is just
thieves who fall out, because you can see from
archive that BobC is another member of
Magnequest gang of thugs.
I'm too sick and angry to discuss this any more.
Raf
Greetings from
Rafael Antonio Ferenghetti
Date: Thu, 12 Apr 2001 18:21:05 -0400
From: "BobC" <bobcx@nyc.rr.com>
Subject: Re: [JN] Filth
- - ----- Original Message -----
From: "PEARL Cust. Service" <custserv@pearl-hifi.com>
To: <sound@lists.io.com>
Sent: Wednesday, April 11, 2001 3:18 PM
Subject: Re: [JN] Filth
> Hello Raphael:
> Not to point any sort of a finger, but I'm the only Joe I'm aware
> of who makes transformers commercially and I assure you that I
> am *not* responsible for your spam problems.
Bill please don't waste your time as this is pure fiction posted by (Henry
A. Pasternack) = (RAF) who just wants to cause trouble here because he is
lonely.
regards
BC
=========================================================================
From: "Phil Sieg" <psieg@nxs.net>
Subject: Re: [JN] Filth
Date: Mon, 16 Apr 2001 18:26:21 -0400
Source: Sound Digest Archive v02.n867
>Even his friend Phil Sieg name Mike LaFevre
> of Magnequest Transformers.
DO NOT twist my words. I did not 'name' Mike, I said I didn't care WHO was
doing it - the discussion doesn't belong on the Joe-Net. And I'm fairly
certain you don't either.
Phil
=========================================================================
From: James Melhuish <james@melhuish.org>
Subject: Re: [JN] Filth, and Single Drivers
Date: Fri, 13 Apr 2001 17:22:12 -0400
Source: Sound Digest Archive v02.n867
I run the Single Driver Website (http://melhuish.org/audio/) which
contains the Full Range Forum (mentioned as Single Driver Conference
by Rafael). I did have some pretty major problems concerning Andre
Jute in the recent past. They have cleared up, thankfully. It takes
a great deal of time to moderate a forum.
Rafael wrote:
Hundreds of people saw the same homosexual filth posted to the Single
Driver Conference. This was at the time that those who stalk Andre
disrupted that list also with other posts from Henry Pasternack,
Michael LaFevre and Bob Chernofsky.
There were pornographic posts on the Full Range Forum, as well as
plenty of attacking of Andre Jute. However, the posts that Henry,
Michael and Bob signed their name to were acceptable. The porn posts
were untraceable. While Henry, Michael, and Bob may have differences
with Andre, I cannot attribute the bad behavior to any of them.
I urge people NOT to write to the Joelist about this matter. It
wastes bandwidth. Thanks.
James
- --
James Melhuish
Single Driver Website http://melhuish.org/audio/
mailto:james@melhuish.org
=========================================================================
From: "Kurt Th. Steffensen" <kurt-steffensen@teliamail.dk>
Subject: [JN] FINAL CF
Date: Wed, 4 Aug 1999 14:28:25 +0300
Source: Sound Digest Archive v02.n220
There are to many misunderstandings , errors etc. , in this debate about CF´s.
I have taking to many things for granted regarding the experience and knowledge
of us Joer´s.
Please , allow me to take it in another contend , this time.
I will use some of Thorstens post to me and the list later , and use it as a oppertunity to cast a l
ittle light on some of the merits of CF´s and clear up some of the misunderstandings.
The Cathode Follower , or any other first degree follower (Fet , SS) is the maximum
best the device can do.
The CF is of no use in it self , however , as it has no amplification.
It has however some other advantage that no other stage has, and these makes it very usefull in appl
ication with other circuits , or simply as the most High Fidelity and wideband stages we can design.
The input impedance of the CF is very high ,(Several Mega to Giga Ohms if needed) the capacitance is
very low , and so is the miller effects.
That makes it very usefull as first stage , in applications in which these merits is important.(Micr
ophones , measuring tools , UHF stages etc)
The output impedance of the CF is very low , (Below 1 Ohm if needed)
and it can be used to drive long cables or difficult output stages/loads.
The frequency responce of the CF can be stretch from DC to several GigaHertz.
And the distortion is well below what can be detected by human ears or measuring
tools , if it is carefull and clever brought out.
The transfere charactheristics curves for a triode as CF´s , can not be seen readily
from the common plate curves , however they can be obtain with the actual CF or
calculated by use of the common curves.
These curves are allmost 90 degrees on the Y-axis , and is so close to the ideal
linearity , that they looks 100% ideal to the eye.
(And practical they are)
Now , what is its use in Audio application , one might ask , as the CF can not amplify.
Well , say we build a ECC 83 stage with a CCS in the anode.
This stage will unloaded amplify close to the optimal , and have the widest frequency
responce and lowest distortion , that the ECC 83 can ever manage.
But the minute we connect this stage to the following , these highly wanted merits
are all gone with the wind.
The amplification willl drop to about 30% , and distortion will rise with several 100%´s ,
and finally the frequency, phase and rise time responce, will all decrease to be within
the audio range.
If we however follows this stage with a CF´s , that is well made , allmost all of these
merits will remain untouched , and we have the best performance that the ECC 83 can ever do.
And belive me , such thing Joes , is VERY audible.
(I would not choose the ECC 83 in the first place , this is only an example)
Another example.
If we are building an output stage with 211´s or 805´s.
(It does not matter to this example if it is SE or PP)
These output tubes are rather difficult to drive , especially the 805´s.
This is due to the fact , that both these tubes draws a little grid current , and lots of
it when driving posetive refering to the Cathodes.
In addition , the input capacitance is high on these tubes.
If driven by a normal stage in which the output is taken from the Anodes ,
the results are poor frequency responce , phase distortion , poor rise time ,
- - bad transient responce and lower output.
The nature of all these unwanted events , produce distortion.
Now , the 211´s can be driven well from the anodes by a common low ri/high current stage such as a 1
2B4 , but we will never achive its maximum performance.
But the 805 is flat out impossible to drive from the anodes, if low distortion is the goal.
Here the CF once again is the solution.
It will drive both type of tubes to the maximum they can perform.
It will only be the natural merits of the output tubes , that sets the limits.
And that is the ideal case , and it can be HEARD !
Further it is possible , to let the CF present the bias to the output stage , and
hereby avoid both the electrolytics and capacitors in the signal path.
That is also a major advantage that can be heard immediately.
Finally it is possible to let the output tubes drive the load (Output transformer) ,
as a CF.
Simply swap the output transformer into the cathode circuit , instead of the
anode circuit. - I know from practical experiments , that the best results is achived
by the same transfer relation in the transf. as if it was meant to be in the Anodes.
It does , however needs a lot higher Peak/Peak Voltage from the driver stages ,
- - this stage is critical , and need to be good designed to achive maximum performence.
The output tubes does , fortunate othervice represent an easy load , to the
driving stage.
Othervice it is often a great sonic advantage to use the CF as the output - line
stage from a pre-amplifier or DAC or similar.
Me , snipped from a previus post:
>> The Z-out is given by:Ri/(u+1) // Rk. Or simply Ri/(u+1) if a CCS is used.
>
>You cannot really use CCS here as you where all the time on about the classic CF, one Resistor in t
he Cathode, one Valve.
- - I only propose how to calculate the Z-out if CCS is used..
The advantage of building the simple CF , with a CCS in the cathode is mainly ,
that it presents an easy load to the PSU.
Therefore the demands to the PSU , is not critical.
It does also decreases distortion , but the distortion in a good CF ,is allready well below what can
be heard , or measured, so in my oponion , this should not be the argument to
imply the CCS.
Further the CCS rise the Z-out , calculated by the formula above.
No capacitors or electrolytics must however ,be used in the CCS circuit , as this will mess the phas
e relation , and loose a major part of the good merits , othervice
achived with the good CF.
I use simple Constant Current Diodes.(=Fets gate+Source connected)
>You have here now done only one thing. You changed the valve from a ECC88 (which is actually capabl
e of operating succesfully in a Common Cathode Stage WITHOUT buffer) to a 6SN7 with (apparently) unb
ypassed Cathode Resistor creating a Stage that cannot be used at all without buffer.
Yes, I have all the way advocated for the simple circuit.
No other components is needed.
If we bypass the Cathodes it is no longer a CF.
>> Distortion of ANY kind , is a tiny fraction of what any other single 6SN7
>> stage can accomplish.
>
>Yup. But that is not because you designed a good Cathode Follower, but because you designed a bad a
mplification stage....
You have misunderstood the whole case.
CF´s can not ever amplify.
I hope by now , that every one understands what a CF really is ?
It does transfer impedance , and can deliver power/current to the next stage.
Used as such , it presents an allmost not existing load to the previus stage ,
and holds the next stage in a rock steady iron hand.
Thorsten:
>In this case the use of an ECC88 as suggested by me is good, as the Ri is lower than the 6SN7 and C
urrent-Capability is good too.
Yes, I used the 6SN7 as an example of what can be achived ,even with this very wellknown and everywh
ere available triode. - Didn´t I mentioned that ?
As you calculated yourself , it is impressing in any contend.
Any tube can be used as a CF. - They will all perform the best the tube can do ,
but some are more suitable as others.
Using the ECC 88 in its best working points , means it will have a rather low bias.
This will be to close at line levels , and the 6SN7 will perform better here.
As the last tip , I can come up with right now , when choosing a tube for the CF´s ,
stage go for the lowest Ri and the tube that can meet the best bias relation , for
the actual application.
The closer to the output stages , the higher the bias is needed ,in order to avoid being close to o
verload situations.
(I strawb for 3-10 times)
Don´t care for u or S , in choosing tubes for CF´s.
It will work perfect if :
1)the bias is high enough
2) is at one of the high lineare spots ,
in the actual working set up
3) Sink the idle current , that is needed to drive the following stage.
This also insures that the cathode resistors are low.
That might seem as quite many things that must be optimized to achive the best CF´s ,
but if only patient and carefull calculations and study of the data is carried out , it is not
that hard , but well worth the effort.
Then finally , Torsten , has the nerve to suggest that I haven´t done any practical
experiments and that I ignore the Valley Wallman and Norman Crowhurst ,
and other socalled proofs of the bad performance of CF´s.
This unpolite , respectless bable gets me so frustrated , that I will allow my self
to speak straight out for the first time in years.
Her it comes , hold on:
Such a green youngster as you Thorsten , should shut your fucking mouth , when an old rat like me is
talking.
Despite of you , I HAVE been there and DONE most of the things you haven´t even thought of yet.
You will threat me with the same respect as I treat you and anyone else , or you simply stay in your
room. (Where ever that is).
An apology will be well recieved.
Now, here comes the facts , Thorsten , cause I have read both the proofs you refere to.
I have seen the out of content qoute , on a website ,announced here at our list.
And I have commented both in the past and in a post to you yesterday or the day before.
None of you can have read the previus nor the following pages of the book you qoute.
The authors are highly recommend CF´s !
But in a chapter for
"DC-amplifiers" !!!!! - the author use an example in which the CF , if build with a high u ,
tube such as 6SL7 in order to achive a slightly better DC deviation , compared to the same 6SL7 with
680K Ohm in the cathode and 1 Mega Ohm in the cathode.
Further these CF´s has a 1MOhm resistor LOOKING in to the grids !!!
They can not pass AC signals , and they never were intented to do.
It is a schoolbook , and the purpose is to enlight.
You guys has only looked at the curves at. fig.11.20b , but haven´t taken the time to
read the text , or even reflect over these very extreeme circuits and curves.
(0,7 V over a 200 V sweep !)
Even the baddest designed CF , will outperform all of the three circuits illustrated ,
when it comes to AC signals beyond 2 Hertz.
And at DC , the deviation that will be a few uVolts , at the output of our Audio
amplifier , will not even pass the output transformer , neither can it even move
the membrane at all.
But never mind , noone would ever use the illustrated circuits for Audio.
The author is worried about the change in filament temp. (The mains were not
particually stable at those days. 1947)
He wants an actual reading of the DC.
(Servo controlled Motors, measuring tools etc.)
Further he reflects over the possibility with constant current diodes , but again
the technology those days , has not yet invented the FET diode.
They had to do with vacuum diodes , unfortuneately also depentent of
temp.
That´s why he build the circuits , and took the characteristics at DC actual level
It is such a good book , Torsten , and much can be learned from it.
But you have to read it and understyand it , before you used it to knock any ones
heads.
If you have cared to read the book , you would have seen the authors recommend
using Cathode followers because of the exact same reasons as I.
Norman Crowhurst , has never been negative about the CF´s , and claimed them as
unusefull or anything.
CF´s are also highly praised by another grand old master :"Cathode Ray".
Normann Crowhurst , has discussed the pros and cons for CF´s as power output
stages , as far as I remembers , he highly recommended these.
This is all in all a stupid debate , because the CF set up , can not avoid being the best the
tube can perform. - It can never be poorer than ANY other use of the tube.
It is the very basic nature of the devices.
If CF´s are considered bad , there is no other circuit left.
CF´s can only be used bad or designed bad , just as any other topology.
I hope now , the true merits of CF´s is wellknown , and that we do not have to hear
about the proofs of their bad performence ever again.
They simply can not behave poorer than any other circuit.
But therefore they CAN`T amplify....Sadly.
- - Sincerely Kurt
=========================================================================
From: Jeff Mai <j.mai.lists@home.com>
Subject: [JN] Final Garage Sale Update
Date: Tue, 17 Jul 2001 20:42:18 -0600
Source: Sound Digest Archive v02.n927
No one made an offer on all of the stuff, so I'm parting it out.
Here's what's left and available. Offers still accepted. This will
be my last post for this stuff, in case any of you were thinking I'd
turn this into the home shopping network.
I'll be emailing each of you that reserved lots within the next hour.
Thanks for the bandwidth.
Jeff
At 10:40 PM -0600 7/14/01, Jeff Mai wrote:
>Links to photos of each lot are provided in the list below. All of
>the prices *do not* include shipping.
>
>Lot #2: http://members.home.com/j.mai.lists/garagesale/101-0102_IMG.JPG
>Large, vintage Hammond plate transformer. Type 720X60 , 250 VA.
>Current model 720 is 1250 VCT @ 300ma, but this would exceed the
>250VA rating. It's exactly the same core size as that model,
>though. Way cool name plate, but some rust. With a little
>refinishing this would look really trick. $30
>
>Lot #3: http://members.home.com/j.mai.lists/garagesale/101-0103_IMG.JPG
>Big Freed Choke. 2.5 HY, 700ma, 43V RMS, 23 ohms, 1000V WV. Cap
>input only, I'm guessing from the RMS rating. $15
>
>Lot #5: http://members.home.com/j.mai.lists/garagesale/101-0105_IMG.JPG
>Dual choke. 2 * 4 HY, 120 ma, 150V RMS, 47 ohms, 300V WV. $15
>
>Lot #9: http://members.home.com/j.mai.lists/garagesale/101-0109_IMG.JPG
>RCA cables. 5 stereo pairs. Cheap stuff except for one Monster
>Cable pair (which was still cheap, just not as cheap.) $5
>
>Lot #10: http://members.home.com/j.mai.lists/garagesale/101-0110_IMG.JPG
>Microphone. Stereo miniplug. Ultra cheap; came with computer.
>I'll throw it in with something else if you want it.
>
>Lot #11: http://members.home.com/j.mai.lists/garagesale/101-0111_IMG.JPG
>A lot of terminated coaxial video cable. One S-VHS cable. $5
>
>Lot #13: http://members.home.com/j.mai.lists/garagesale/101-0113_IMG.JPG
>Wall wart. 14 VDC @ 850 ma. $5
>
>Lot #14: http://members.home.com/j.mai.lists/garagesale/101-0114_IMG.JPG
>Big pile 'o caps. Except for the two Techtronix branded caps at
>left, they're pretty much all electrolytics. Most of them are NOS
>low voltage. $10
>
>Lot #15: http://members.home.com/j.mai.lists/garagesale/101-0115_IMG.JPG
>Odd tube sockets. A nine pin mini Vector socket and two 7 pin mini
>adapters with test points. Freebie with other stuff.
>
>Lot #18: http://members.home.com/j.mai.lists/garagesale/101-0118_IMG.JPG
>Misc unknown transformers. Two in front are fil trans I bought for
>6B4Gs. They are either 12.6VCT @ 0.6 amp or 6.3VCT @ 1.2 amp. The
>others are unmarked and unknown. $10
>
>Lot #19: http://members.home.com/j.mai.lists/garagesale/101-0119_IMG.JPG
>Pair UTC 20VCT fil trans. $10
>
>Lot #21: http://members.home.com/j.mai.lists/garagesale/101-0121_IMG.JPG
>Unknown chokes. $5
>
>Lot #22: http://members.home.com/j.mai.lists/garagesale/101-0122_IMG.JPG
>NOS Thordarson Fil Trans. 6.3VCT @ 0.6 amps. $5
>
>Lot #29: http://members.home.com/j.mai.lists/garagesale/101-0129_IMG.JPG
>Surgistor? Unknown pot with switch. 100 ohm 10 turn WW pot. Misc
>ICs. Throw in.
>
>Lot #30: http://members.home.com/j.mai.lists/garagesale/101-0130_IMG.JPG
>Big unknown plate and fil trans. It's the same size as the Hammond
>above. I measured it once upon a time and it was well over 1000VCT
>with no load. $20
>
>Lot #31: http://members.home.com/j.mai.lists/garagesale/101-0131_IMG.JPG
>Avel Toroid. 18V + 18V. Dual 120V primaries. Model D4030. $15
>
>Lot #33: http://members.home.com/j.mai.lists/garagesale/101-0133_IMG.JPG
>Unknown trans. Decent sized. I'll include with lot #18.
>
>Lot #34: http://members.home.com/j.mai.lists/garagesale/101-0134_IMG.JPG
>Pair mil surplus plate and fil trans. 720VCT @ 125 ma, 6.3VAC @
>3.5A, 6.3VAC @ 2A. Dual 115V primaries. Two terminals were broken
>off one unit. I repaired with wire. Work fine. Great for
>monoblock amps. $30
>
>Lot #35: http://members.home.com/j.mai.lists/garagesale/101-0135_IMG.JPG
>Huge WE 354A MV rectifier. Base loose. I doubt it works but don't
>know for sure. Free.
>
>Lot #36: http://members.home.com/j.mai.lists/garagesale/101-0136_IMG.JPG
>Delco 50 tube. Looks and tests as new. Let's call it lightly used. $100
>
>Lot #40: http://members.home.com/j.mai.lists/garagesale/101-0140_IMG.JPG
>NIB Cetron 323B MV thyratron. $5
>
>Lot #41: http://members.home.com/j.mai.lists/garagesale/101-0141_IMG.JPG
>Pair RCA 80 rectifiers. Used. One boxed. $12
>
>Lot #42: http://members.home.com/j.mai.lists/garagesale/101-0142_IMG.JPG
>Misc tubes. 3 * NEC 6AR5, NEC 12AT7, NEC 6CA4, all pulls. 6D6,
>6DM4, 2X2, 2C53, 2 * 6F4. $5
>
>Lot #45: http://members.home.com/j.mai.lists/garagesale/101-0145_IMG.JPG
>4 NOS Tung-Sol 6AX5GT. Nice little rectifiers with 6.3VAC fils. $10
>
>Lot #46: http://members.home.com/j.mai.lists/garagesale/101-0146_IMG.JPG
>10 Misc 6AC7. Mostly GE and Ken-Rad despite what the boxes say.
>Some rattle a bit. No way to test. I'll guarantee 4 are good
>(unless I wind up giving them away, of course.) $7
>
>Lot #48: http://members.home.com/j.mai.lists/garagesale/101-0148_IMG.JPG
>2 NOS 12AX7. Stinky boxes. $10
>
>Thanks for the bandwidth.
>
>Jeff
=========================================================================
From: Rich <rconte@attglobal.net>
Subject: [JN] Final: Jensen BL250 Information
Date: Tue, 25 Apr 2000 08:56:51 -0400
Source: Sound Digest Archive v02.n528
Per Vintage Audio Trader (KerryB)
"Hi Rich,
The Jensen TRIPLEX system is a three-way component package
in a ( ' Bass Ultraflex enclosure for 15" loudspeakers ' ) ported
cabinet. It is a 1956 Jensen system second only to the Imperial, using
exactly the same component package. The ported cabinet is smaller and
therefore considered a
' compromise for convenience ', relative to the Imperial. I attached a
list taken from Jensen tech. manual 1065 which gives the component model
numbers and names.
Onken of Japan copied this cabinet design in the
seventies. They built a two-part cabinet version using ultra-hgh grade
materials that's considered the best ported box for 15" speakers.
It's response is about +-3dB between 35 and 20kHz. Like
any of the speakers of it's time, an input of 35 watts or so was
considered max power. You can get levels in excess of 100 dBs with a 3
watt triode amp so there's no need for, or advantage to, using anything
more powerful.
Thanks for your kind words about my page. I would love to
have pictures - of your Imperials as well, if possible. Send them to;
Kerry B.
Xover - 600Hz for Midrange and 4Khz for Hypex Super Tweeter.
"
By the way, I sell high quality laser-printed replicas of
the Jensen manual - which includes plans for the entire '50s lineup of
Jensen systems and cabinets - for $21.00 ( includes U.S. shipping ).
jensen.jpg ( jpg image attached )
http://community.webtv.net/KerrB
VINAUDTRDR'S HOME PAGE
Subject:
Help ID a Jensen Triplex with 15" Concert Bass unit and mid
horn and high
horn
Date:
Mon, 24 Apr 2000 11:19:49 -0400
From:
Rich <rconte@attglobal.net>
Organization:
N/A
To:
KerrB@webtv.net
Hi Dear Sir,
I love the page and have a ?, I found a large, I mean large, almost like
a Jensen Imperial Horn, But not, has two large transformers in it and a
massive Xover, a JENSEN TRIPLEX...It sound wonderful...do you have any
info on it or any idea of it's spec's and power range...I own a pair of
Jensen Imperial Horns and it is similar, brass H-F and M-F coils but
vented on the side backs and horn loaded mid and high...1812 overture is
a blast. The bass is a 15" JENSEN CONCERT ALNICO unit with blue and
grey lettering HIGH FIDELITY, same with horns.
Any kind help is greatly appreciated and I will send you a picture if
you would like one for the web page, snail mail, no camera, but I have
the closeups if the unit serial # and how to use info. on back...
Sincerely,
Rich Conte
Vintage speaker buff and restoration hound...cabinets in mahogany
=========================================================================
From: "Carter Hendricks" <carter@i1.net>
Subject: Re: [JN] Final: Jensen BL250 Information
Date: Tue, 25 Apr 2000 21:55:25 -0500
Source: Sound Digest Archive v02.n529
> Per Vintage Audio Trader (KerryB)
>
>...Onken of Japan copied this cabinet design...
I built an Ultraflex cabinet for a Jensen driver,
but I think this is a bit misleading. The Onken
is an elaboration of the original Jensen design,
much further developed for specific [better?]
drivers. The Ultraflex was a generic cabinet
suitable for a range of drivers.
--Carter
=========================================================================
From: Rich <rconte@attglobal.net>
Subject: Re: [JN] Final: Jensen BL250 Information
Date: Wed, 26 Apr 2000 08:35:44 -0400
Source: Sound Digest Archive v02.n530
Hi Carter,
Thanks so kindly for the elaboration and experience comments...it's good
to see more on the Onken.
I copied from two reliable sources the information presented to me, so
it's good to see that the information needed tweaking, much like
changing out bypass caps on an output stage for Elna v. generic type
caps...;-)
Anyway, cheers and the Onken seems to be a derivation of the Jensen
UltraFlex not an exact copy, I cite the SP articles...thanks again for
the further information on this topic...it is a very interesting cabinet
and design...
Cheers.
Carter Hendricks wrote:
>
> > Per Vintage Audio Trader (KerryB)
> >
> >...Onken of Japan copied this cabinet design...
>
> I built an Ultraflex cabinet for a Jensen driver,
> but I think this is a bit misleading. The Onken
> is an elaboration of the original Jensen design,
> much further developed for specific [better?]
> drivers. The Ultraflex was a generic cabinet
> suitable for a range of drivers.
>
> --Carter
=========================================================================
From: Torsten.Loesch@enhar-ha.nthames.nhs.uk
Subject: Re(2): [JN] Finally - the Fuge Amplifier
Date: 16 Feb 1999 09:43:08 +0000
Source: Sound Digest Archive v02.n045
Hi there,
> My simple question is: is there a cheaper alternative to the E810F in the
> regulator circuit?
EF184. But I'd say the E810F will sound better. The Valve is not getting
stressed at all in this position. Livespan should be >> 40,000h in this
position.... All other Valves will wear out faster.
Later Thorsten
=========================================================================
From: "Sellek, Grant (TSA)" <Grant.Sellek@roads.sa.gov.au>
Subject: RE: [JN] Finally - the Fuge Amplifier
Date: Tue, 16 Feb 1999 10:07:30 +1030
Source: Sound Digest Archive v02.n045
Thanks Torsten, it is really good of you to share this, especially given its
unusual topology.
My simple question is: is there a cheaper alternative to the E810F in the
regulator circuit?
Grant Sellek
Adelaide, Australia
grant.sellek@roads.sa.gov.au
~ -----Original Message-----
~ From: Torsten.Loesch@enhar-ha.nthames.nhs.uk
~ [mailto:Torsten.Loesch@enhar-ha.nthames.nhs.uk]
~ Sent: Monday, 15 February 1999 10:39 pm
~ To: sound@lists.io.com
~ Subject: [JN] Finally - the Fuge Amplifier
~
~ The "Fuge" project was eventually decided by me to be the
~ "ultimate" 300B SE Amplifier.
~
=========================================================================
From: evaguido <EvaGuido@iaehv.nl>
Subject: RE: [JN] Finally - the Fuge Amplifier
Date: Tue, 16 Feb 1999 18:18:16 +0100
Source: Sound Digest Archive v02.n045
Grant,
>My simple question is: is there a cheaper alternative to the E810F in the
>regulator circuit?
I think E80F will do as well
Guido
>Grant Sellek
>Adelaide, Australia
>grant.sellek@roads.sa.gov.au
>
>
>~ -----Original Message-----
>~ From: Torsten.Loesch@enhar-ha.nthames.nhs.uk
>~ [mailto:Torsten.Loesch@enhar-ha.nthames.nhs.uk]
>~ Sent: Monday, 15 February 1999 10:39 pm
>~ To: sound@lists.io.com
>~ Subject: [JN] Finally - the Fuge Amplifier
>~
>~ The "Fuge" project was eventually decided by me to be the
>~ "ultimate" 300B SE Amplifier.
>~
>
>
=========================================================================
From: Simon Busbridge <S.C.Busbridge@bton.ac.uk>
Subject: Re: [JN] Finally - the Fuge Amplifier
Date: Wed, 17 Feb 1999 16:27:47 +0000 (BST)
Source: Sound Digest Archive v02.n047
Hi Torsten,
I'm curious about the "de-hum" pot on your fuge powersupply. Can you
please tell us more?
Simon
Simon Busbridge, BSc(Hons) PhD CPhys MInstP
School of Engineering
University of Brighton
Lewes Road
Moulsecoomb
Brighton BN2 4GJ
UNITED KINGDOM
Tel: 0044 (0)1273 642542
Fax: 0044 (0)1273 642327/642301
e-mail: s.c.busbridge@bton.ac.uk, scbusbridge@hotmail.com
On 15 Feb 1999 Torsten.Loesch@enhar-ha.nthames.nhs.uk wrote:
> Hi all,
>
> I should insert here a long list of Credits, but I'd just like to thank
> everyone here, on rec.audio.tubes and others for their help, assistane and
> input.
>
> The "Fuge" project was eventually decided by me to be the "ultimate" 300B SE
> Amplifier.
>
> I know some will disagree, but I feel the results certainly are way beyond
> the usual.
>
> The Input/Driver Stage is what I have dubbed "Super-Mu-Stage" (SuMu). It uses
> a mixture of ideas gleamed of various people to make a "ultimate"
> driver-stage.
>
> The upper Valve of this "modified SRRP" is cascoded (as shown to me first by
> Allen Wright). It also uses a constant-current-load (as per many suggestions)
> almost entierly removing the sound problems of this configuration. It makes
> for a very low drive-impedance allowing some positive grid drive.
>
> The constant-current source (made up from a 2SK147 BL and a resistor) is also
> the Anode load for the lower Valve, so this Valve sees a load of appx. 2
> Megaohm. Unless a significant load is present, the whole stage operates under
> constant current conditions.
>
> If used as a Line-Stage, about 70V RMS can be provided into a 10k Load, the
> Gain is about 43 and into a IEC Load (10k // 1nF) we get about 600kHz upper
> cutoff.... THD is dominted by 2nd harmonics and is very low (below what I can
> measure reliably).
>
> It should be obvious that a wide range of applications and Variants of this
> circuit is possible.
>
> For this Amplifier, the SuMu stage is used in a modified Loftin White
> Circuit.
>
> In order to avoid too much DC drift, there is a bit of positive feedback from
> Grid of the 300B to the Cathode of the 5842 is used. Both +B and -B are
> regulated. The +B Regulater is based on the JC Verdier Regulator from Sound
> Practices. The -B Regulator is a simple Shunt-regulator of my own doing. The
> PSU as shown is for a Stereo Amp.
>
> All capacitors apart from the main reservoir capacitors in the PSU and the
> bypass on the Zenner in the -B Regulator are polypropylene, a Mixture of
> Ansar (PSU Filtering) and ICW (secondary Signalpath and regulators). The PSU
> Caps are Nippon Chemicon long live, low-z units.
>
> All filaments are current-regulated using overall 8psc LM317 3-pin jobs. In
> each case the - Side of the Filament is tied to one of the Grounds. The
> 300B's and 5687 Filaments go to the (virtual) 0V "power-ground". the 5842
> Filaments are tied to the -B ground, which is actually the Signal Ground for
> the OPT's secondary and the input.
>
> Signal-path wiring is solid silver in teflon sleeving and the PSU/Heater
> Wiring is AC Mains Copper 1mm (electrical safety).
>
> I currently use the 300B (Svetlana) at 375V +B (370V Anode) and about
> 60-65mA. The Output transformer is nominally 3.6k Ohm.
>
> As for DC Stability, after about 5min the Anode current reaches 55ma and will
> over the next hour or so reach the final 65mA.
>
> The sound is something else.
>
> It must be heard to be believed. Transparent, fast, with a lovely tone. The
> Bass has a speed, depth and impact reminicent of Krell (no Joke). I'm not
> sure if there is not possibly the faintest trance of "electronicsm" in the
> sound, but it could be the recordings.
>
> Listening to original Jazz and Classical Recordings from the Golden Aera
> (like Miles Davis KOB on Columbia, Dave Brubeck Quartett live in the Carnegy,
> Dallas Symphony Orchestra on Turnabout Records or any of the great female
> Jazz-Vocals) the sound is as natural as I have ever heard....
>
> Anyway. I would be mightily impressed by this Amp, because I designed it. We
> will be doing some shootouts against Croft modified Quad II's and a 2A3
> Push-Pull (made according to the Gospel with 6SN7 drivers, Valve
> rectification and conventional LC Supplies). I do expect a Victory by a good
> margin, but there's only one way to find out....
>
> Certainly this Amp makes my (heavily modified) Marantz Amplifier sound
> broken....
>
> Lastly, apaologies for sending these binaries, but really can't draw this out
> in ASCII.
>
> Later Thorsten
>
=========================================================================
From: Torsten.Loesch@enhar-ha.nthames.nhs.uk
Subject: Re(2): [JN] Finally - the Fuge Amplifier
Date: 17 Feb 1999 17:01:26 +0000
Source: Sound Digest Archive v02.n047
Hi there,
> I'm curious about the "de-hum" pot on your fuge powersupply. Can you
> please tell us more?
Very old Trick.
By injecting a little of the ripple Voltage on the raw +B Rail into the
screen-grid of the Pentode, we can cancel out more ripple than we would be
able to with the regulator alone.... You will need a pair of really sensitive
Headphones or a sensitive Scope to do that effectively though.
Later Thorsten
=========================================================================
From: Simon Busbridge <S.C.Busbridge@bton.ac.uk>
Subject: Re: Re(2): [JN] Finally - the Fuge Amplifier
Date: Wed, 17 Feb 1999 17:15:08 +0000 (BST)
Source: Sound Digest Archive v02.n047
OK, many thanks.
Looks as though you are really into cancellations!!
Simon
Simon Busbridge, BSc(Hons) PhD CPhys MInstP
School of Engineering
University of Brighton
Lewes Road
Moulsecoomb
Brighton BN2 4GJ
UNITED KINGDOM
Tel: 0044 (0)1273 642542
Fax: 0044 (0)1273 642327/642301
e-mail: s.c.busbridge@bton.ac.uk, scbusbridge@hotmail.com
On 17 Feb 1999 Torsten.Loesch@enhar-ha.nthames.nhs.uk wrote:
> Hi there,
>
> > I'm curious about the "de-hum" pot on your fuge powersupply. Can you
> > please tell us more?
>
> Very old Trick.
>
> By injecting a little of the ripple Voltage on the raw +B Rail into the
> screen-grid of the Pentode, we can cancel out more ripple than we would be
> able to with the regulator alone.... You will need a pair of really sensitive
> Headphones or a sensitive Scope to do that effectively though.
>
> Later Thorsten
>
=========================================================================
From: Torsten.Loesch@enhar-ha.nthames.nhs.uk
Subject: Re(2): Re(2): [JN] Finally - the Fuge Amplifier
Date: 17 Feb 1999 17:37:35 +0000
Source: Sound Digest Archive v02.n047
Hi there,
I wrote:
> > By injecting a little of the ripple Voltage on the raw +B Rail into the
> > screen-grid of the Pentode, we can cancel out more ripple than we would
be
> > able to with the regulator alone....
Simon wrote:
> Looks as though you are really into cancellations!!
Not at all. But it works and is essentially free.... The result of using this
PSU (optimised) and of using current regulated DC Heaters (everywhere but the
regulator Circuit) is an Amplifier with a Noisefloor significantly below
0.1mV (broadband) on the Output. I need a more sensitive 'scope to do the
fine-tuning....
That was the partipolitical Broadcast of the "We want quiet Amplifiers"
party. Lowthwer and Horn Speaker useres are invited to join....
Ciao Thorsten
=========================================================================
From: Simon Busbridge <S.C.Busbridge@bton.ac.uk>
Subject: Re: Re(2): Re(2): [JN] Finally - the Fuge Amplifier
Date: Wed, 17 Feb 1999 17:55:57 +0000 (BST)
Source: Sound Digest Archive v02.n047
Thanks Torsten
My regulated supply uses the 6B4G and there is some hum on the output
which I would like to reduce. So you enspire me on....
Best wishes
Simon
Simon Busbridge, BSc(Hons) PhD CPhys MInstP
School of Engineering
University of Brighton
Lewes Road
Moulsecoomb
Brighton BN2 4GJ
UNITED KINGDOM
Tel: 0044 (0)1273 642542
Fax: 0044 (0)1273 642327/642301
e-mail: s.c.busbridge@bton.ac.uk, scbusbridge@hotmail.com
On 17 Feb 1999 Torsten.Loesch@enhar-ha.nthames.nhs.uk wrote:
> Hi there,
>
> I wrote:
>
> > > By injecting a little of the ripple Voltage on the raw +B Rail into the
> > > screen-grid of the Pentode, we can cancel out more ripple than we would
> be
> > > able to with the regulator alone....
>
> Simon wrote:
>
> > Looks as though you are really into cancellations!!
>
> Not at all. But it works and is essentially free.... The result of using this
> PSU (optimised) and of using current regulated DC Heaters (everywhere but the
> regulator Circuit) is an Amplifier with a Noisefloor significantly below
> 0.1mV (broadband) on the Output. I need a more sensitive 'scope to do the
> fine-tuning....
>
> That was the partipolitical Broadcast of the "We want quiet Amplifiers"
> party. Lowthwer and Horn Speaker useres are invited to join....
>
> Ciao Thorsten
>
=========================================================================
From: Torsten.Loesch@enhar-ha.nthames.nhs.uk
Subject: [JN] Finally - the Fuge Amplifier - public premiere
Date: 15 Feb 1999 12:09:12 +0000
Source: Sound Digest Archive v02.n044
- --__boundary__15:02:1999_12:19:16_(18035)
Content-Type: text/plain;
charset=iso-8859-1
Content-Transfer-Encoding: 7bit
Hi all,
I should insert here a long list of Credits, but I'd just like to thank
everyone here, on rec.audio.tubes and others for their help, assistane and
input.
The "Fuge" project was eventually decided by me to be the "ultimate" 300B SE
Amplifier.
I know some will disagree, but I feel the results certainly are way beyond
the usual.
The Input/Driver Stage is what I have dubbed "Super-Mu-Stage" (SuMu). It uses
a mixture of ideas gleamed of various people to make a "ultimate"
driver-stage.
The upper Valve of this "modified SRRP" is cascoded (as shown to me first by
Allen Wright). It also uses a constant-current-load (as per many suggestions)
almost entierly removing the sound problems of this configuration. It makes
for a very low drive-impedance allowing some positive grid drive.
The constant-current source (made up from a 2SK147 BL and a resistor) is also
the Anode load for the lower Valve, so this Valve sees a load of appx. 2
Megaohm. Unless a significant load is present, the whole stage operates under
constant current conditions.
If used as a Line-Stage, about 70V RMS can be provided into a 10k Load, the
Gain is about 43 and into a IEC Load (10k // 1nF) we get about 600kHz upper
cutoff.... THD is dominted by 2nd harmonics and is very low (below what I can
measure reliably).
It should be obvious that a wide range of applications and Variants of this
circuit is possible.
For this Amplifier, the SuMu stage is used in a modified Loftin White
Circuit.
In order to avoid too much DC drift, there is a bit of positive feedback from
Grid of the 300B to the Cathode of the 5842 is used. Both +B and -B are
regulated. The +B Regulater is based on the JC Verdier Regulator from Sound
Practices. The -B Regulator is a simple Shunt-regulator of my own doing. The
PSU as shown is for a Stereo Amp.
All capacitors apart from the main reservoir capacitors in the PSU and the
bypass on the Zenner in the -B Regulator are polypropylene, a Mixture of
Ansar (PSU Filtering) and ICW (secondary Signalpath and regulators). The PSU
Caps are Nippon Chemicon long live, low-z units.
All filaments are current-regulated using overall 8psc LM317 3-pin jobs. In
each case the - Side of the Filament is tied to one of the Grounds. The
300B's and 5687 Filaments go to the (virtual) 0V "power-ground". the 5842
Filaments are tied to the -B ground, which is actually the Signal Ground for
the OPT's secondary and the input.
Signal-path wiring is solid silver in teflon sleeving and the PSU/Heater
Wiring is AC Mains Copper 1mm (electrical safety).
I currently use the 300B (Svetlana) at 375V +B (370V Anode) and about
60-65mA. The Output transformer is nominally 3.6k Ohm.
As for DC Stability, after about 5min the Anode current reaches 55ma and will
over the next hour or so reach the final 65mA.
The sound is something else.
It must be heard to be believed. Transparent, fast, with a lovely tone. The
Bass has a speed, depth and impact reminicent of Krell (no Joke). I'm not
sure if there is not possibly the faintest trance of "electronicsm" in the
sound, but it could be the recordings.
Listening to original Jazz and Classical Recordings from the Golden Aera
(like Miles Davis KOB on Columbia, Dave Brubeck Quartett live in the Carnegy,
Dallas Symphony Orchestra on Turnabout Records or any of the great female
Jazz-Vocals) the sound is as natural as I have ever heard....
Anyway. I would be mightily impressed by this Amp, because I designed it. We
will be doing some shootouts against Croft modified Quad II's and a 2A3
Push-Pull (made according to the Gospel with 6SN7 drivers, Valve
rectification and conventional LC Supplies). I do expect a Victory by a good
margin, but there's only one way to find out....
Certainly this Amp makes my (heavily modified) Marantz Amplifier sound
broken....
Lastly, apaologies for sending these binaries, but really can't draw this out
in ASCII.
Later Thorsten
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R3sYmETYyHsVeFslpUmThGFNA46pOJNsKB+NGXgyeJjQEzPneG8tGF7vaJiRKXr1mI9jmGP7
tpf4ZIEPVpWtSUhceYBQOJddiZrrhHt0VJLh2ILuxmmXGZEBZpCLJpiYeZHiFn8WqId81pH2
KEg9VpsZqJvIuZDGCDbJZ5ljxVWBqHC3uZInGYhCVReA27N307KU2HWK0+eJSph+7hmKTwlz
P0mU4ld+OpOU+NlZZJaf/OlMVvGfABqgAjqgBFqgBnqgCJqgCrqgDNqgDvqgEBqhEjqhFFqh
FnqhGKoQAQEAOw==
- --__boundary__15:02:1999_12:19:16_(18035)--
=========================================================================
From: StepHydro@aol.com
Subject: Re: [JN] Finally - the Fuge Amplifier - public premiere
Date: Mon, 15 Feb 1999 10:41:05 EST
Source: Sound Digest Archive v02.n045
Thorsten,
My computer says that the file you sent *isn't* MIME encoded. Would you please
tell me what the format is so I can change the extension and try to view it
directly?
Are there any changes from what you sent me two weeks ago? If not, then I have
it already.
Thanks/Carron
=========================================================================
From: Torsten.Loesch@enhar-ha.nthames.nhs.uk
Subject: Re(2): [JN] Finally - the Fuge Amplifier - public premiere
Date: 16 Feb 1999 09:48:31 +0000
Source: Sound Digest Archive v02.n045
Hi there,
> My computer says that the file you sent *isn't* MIME encoded. Would you
> please tell me what the format is so I can change the extension and try
> to view it directly?
All attachments where gif Graphics.
> Are there any changes from what you sent me two weeks ago?
Yes. Some minor but important "bugfixes". The original Circuit had a tendency
to drift heavily with time....
I had to introduce some positive feedback (Loftin White style, but not quite
- - see if you can spot it) to get the thing stable. It now is within 5mA of
the nominal Operating point (65mA) in under 10 min and remains fairly stable
after that, reaching the nominal 65mA within about an hour.
Later Thorsten
=========================================================================
From: Torsten.Loesch@enhar-ha.nthames.nhs.uk
Subject: Re(2): [JN] Finally - the Fuge Amplifier - public premiere
Date: 17 Feb 1999 10:34:14 +0000
Source: Sound Digest Archive v02.n046
Guido,
> This is inb line with my philosopy: make a very low distortion driver, and
> let the output tube (last stage) dominate the thd
Exactly. I know a few Joes are hot on distortion cancellation, but it works
only for even harmonics and I still believe that two wrongs do not make one
right....
> Why no shunt for the +B ?
!!!! With 180mA consumption as shown and reserves left in for using VV52's or
KR 300BXL's I'd need a Shunt Regulator that will allow > 280mA Shunt Current
at 450V +B. That makes for a cool 126W to dissipate somewhere. I think
not....
> >>All filaments are current-regulated using overall 8psc LM317 3-pin jobs.
In
> >>each case the - Side of the Filament is tied to one of the Grounds. The
> >>300B's and 5687 Filaments go to the (virtual) 0V "power-ground". the 5842
> >>Filaments are tied to the -B ground, which is actually the Signal Ground
> >>for the OPT's secondary and the input.
>
> What is the condition for the shunt ? adjust current such that 5.0 V for a
> 300b is achieved ? Why a shunt ?
Not Shunt. Series Current regulator. Simple 317T with a 1 Ohm Resistor from
Output to Adjust. + Fil is taken from the Adj Pin. I adjust the Voltage on
the 300B to be close to 5V by using some resistors in parallel to the
Filaments to "bleed" off the Excess current (1.25A instead of 1.2A). There is
also a modest value (4.7uF) Filmcap as bypass directly on the Socket.
> The Svetlana is good value for money ! I found 300b's sound better at +B
> of 400 V and little up
I prefered the sound at lower Voltages! Actually, there was comparably little
difference. So my 375V +B do me just fine now.... I can go all the way up to
450V +B if I want to....
> >>As for DC Stability, after about 5min the Anode current reaches 55ma and
> >>will over the next hour or so reach the final 65mA.
>
> My favourite current is about 80 mA to 90 mA
Again, I started at this high current and Voltage (440V Anode and 80mA
Current). Dropping it to the values above did not result in much worse sound.
And at this Operating Point the 300B's should last positively for ages....
> >>It must be heard to be believed. Transparent, fast, with a lovely tone.
The
> >>Bass has a speed, depth and impact reminicent of Krell (no Joke).
>
> Actually it might be a compliment :-)
For an SE Amp I believ it is....
> What other 300b's did you hear ?
Chinese (Shuang) and Sovtek. The Svetlana positively cream them.
> Be careful with shoot outs against a good 300b amplifier....
What is a "good" 300B Amp? Certainly the classic 6SN7/300B/5U4G Circuit is
absolutely OUTCLASSED! I have had this type of Amp around for a few times....
> >>Certainly this Amp makes my (heavily modified) Marantz Amplifier sound
> >>broken....
>
> the next challenge is to get the Marantz at a decent level....
It's already pushed as far as I can. It's sand of course....
Was compared to Krell KAS-50, Naim and a few other less well known Amp's.
With the (now defunked) battery Supply it outperformed the Krell KAS-50 on
all accounts.
Ciao Thorsten
=========================================================================
From: "Le Cleac'h J.-M." <lecleach@cgi.ensmp.fr>
Subject: Re. [JN] Finally - the Fuge Amplifier - public premiere
Date: Wed, 17 Feb 1999 17:21:25 +0100
Source: Sound Digest Archive v02.n047
- ----------
> De : Torsten.Loesch@enhar-ha.nthames.nhs.uk
> Date : mercredi 17 février 1999 11:34
>
> Guido,
>
> > This is in line with my philosopy: make a very low distortion driver,
and
> > let the output tube (last stage) dominate the Thd
>
> Exactly. I know a few Joes are hot on distortion cancellation, but it
works
> only for even harmonics and I still believe that two wrongs do not make
one
> right....
Hello,
In my Shabda amplifier the philosophy I used was even more severe:
make a very low distortion driver + make a very low distortion stage.
(result THD = 0.045% at 400Hz 1watt without any negative feedback)
But in fact this amplifier while possessing a THD nearly 10 times lesser
than a WE91 type amplifier that use cancellation possess the same harmonic
spectrum and sounds very similar...
so my opinion is that the topology doesn't matter, there is different ways
to reach the goal of a natural sound, cancellation is one.
Best regards,
Jean-Michel Le Cleac'h, Paris, France
=========================================================================
From: sschenkel@juno.com
Subject: Re: [JN] Finally - the Fuge Amplifier - public premiere
Date: Wed, 3 Mar 1999 16:52:19 -0800
Source: Sound Digest Archive v02.n066
Have for sale...
Triad-Utrad HS 54 Pri: 20K & 5K
Sec 600 -250 - 150 - 62.5 ohms $20.00ea
UTC LS 33 Pri: 500 - 333 - 200 - 125 - 50 ohms
Sec500 - 333 - 200 - 125 - 50
30 - 20 - 15 - 10 - 7.5 - 5 - 2.5 -
1.2
ohms $ 37.50
Basler Toroid Pri 120Vac
Sec 2X 52V 2X 10V 20V and 6.6V
300Watt 60 cycles
$29.95
Any interest?
Steve
ApexJr
www.aviastar.net/apexjr
___________________________________________________________________
You don't need to buy Internet access to use free Internet e-mail.
Get completely free e-mail from Juno at http://www.juno.com/getjuno.html
or call Juno at (800) 654-JUNO [654-5866]
=========================================================================
From: Horn Nut <hornnut@home.com>
Subject: [JN] Finally...Triodes!
Date: Sun, 24 Sep 2000 22:42:58 -0600
Source: Sound Digest Archive v02.n671
After 7 years of reading SP, 4 years of mostly lurking here on
Joelist and a year after receiving my B-Glow kit from Doc Bottlehead,
I'm listening to my first taste of triodes!!!!! Many things have
stood in the way (mostly lack of time and horn speaker fiddling) but
finally....success! It took 5 inches of snow, no electricity and a
downed power line blocking my car to create a free block of time.
I guess I was charmed in that the amp (only one finished) passed the
smoke test and is making music without any problems. This was no
thanks to the kit assembly instructions which had several serious
wiring errors in them. Fortunately, my exposure to SP and this list
over the last few years allowed me to spot them immediately. Thanks!
Sounds great, but it's a bit difficult for me to make any specific
comments. The music is distracting me from writing this, so that's a
good sign. I'll definitely be finishing up the second amp this week!
Listening in mono has me wondering, is there any way to electrically
recreate a meaningful 3rd central channel from 2 channels? What
about using DSP? 2 channel stereo reproduction definitely has
problems. I've noticed this before when I've listened to my horns in
mono.
Well, back to listening!!
Jeff
=========================================================================
From: John Levreault <jlevro@mediaone.net>
Subject: Re: [JN] Finally...Triodes!
Date: Mon, 25 Sep 2000 09:23:29 -0400
Source: Sound Digest Archive v02.n671
Horn Nut wrote:
>
> Listening in mono has me wondering, is there any way to electrically
> recreate a meaningful 3rd central channel from 2 channels? What
> about using DSP? 2 channel stereo reproduction definitely has
> problems. I've noticed this before when I've listened to my horns in
> mono.
See "The Soul of Sound, Part VIII: Acoustical Perspectives" by Lynn
Olson in _Positive Feedback_, Vol. 6, No. 1. (This might be on his
website.) He recommends the following "equal energy matrix":
"Left Amp = +0.967 Left, -0.259 Right
Center Amp = +0.707 Left, +0.707 Right
Right Amp = -0.259 Left, +0.967 Right"
JL, school librarian
=========================================================================
From: "Gary E. Kaufman" <gkaufman@bu.edu>
Subject: [JN] Finally updated the web page....
Date: Thu, 3 Aug 2000 01:19:20 -0400
Source: Sound Digest Archive v02.n616
I finally got around to updating my web page, take a peek if you need a
break from the solder fumes!
- Gary
EMAIL: gkaufman@the-planet.org
Web: http://www.the-planet.org
=========================================================================
From: "Chris Vryonides" <chrisvryonides@hotmail.com>
Subject: [JN] Final Music-6 battery powered amps
Date: Wed, 03 Oct 2001 08:56:13 +0000
Source: Sound Digest Archive v02.n987
Hi all
As in "Final" the brand...
Anyone know which power op-amp is used in these? All I know is that it's a
commonly available pentawatt package device...
http://www.walrus.co.uk/final/final.htm
shows these and some rather large horns...
I know, it's not vacuum but evil integrated silicon, but I need 6 reasonable
sounding channels for under £50 + what I have in the junkbox. Don't ask...
Thanks very much,
CV
_________________________________________________________________
Get your FREE download of MSN Explorer at http://explorer.msn.com/intl.asp
=========================================================================
From: Thorsten.Loesch@haringey.nhs.uk
Subject: RE: [JN] Final Music-6 battery powered amps
Date: 05 Oct 2001 16:35:15 +0100
Source: Sound Digest Archive v02.n988
Hi,
> Anyone know which power op-amp is used in these?
Don't know fpr sure, but I believe LM1875. You might want to check this discussion group on the whol
e subejct:
http://pub4.ezboard.com/ffakeidsfrm1
Also this website might be of interrest:
http://www.interlog.com/~cfraser/Gainclonehome.htm
Later T
=========================================================================
From: "Bert Doppenberg" <lowther@wxs.nl>
Subject: [JN] Final results of the Oris 150 horn/PM4
Date: Sun, 25 Apr 1999 21:42:32 +0200
Source: Sound Digest Archive v02.n131
Hello All,
To keep you informed, I improved the horn a lot due several changes.
Look at www.lowther.nl/oris-pictures for some detailed photo's.
If you'll need more information, just ask! ;-)
Regards,
Bert,
- ------
E-mail:
Business : BD-Design@lowther.nl
Private : BD@lowther.nl
Lowther Club Holland : LCH@lowther.nl
Homepage : http://www.lowther.nl
Tel./Fax: (0341) 254500 Mobile: (06) 51242990
=========================================================================
From: "Bert Doppenberg" <lowther@wxs.nl>
Subject: [JN] Final results of the Oris 150 horn/PM4
Date: Mon, 26 Apr 1999 00:47:41 +0200
Source: Sound Digest Archive v02.n131
Hello all again,
I did send a wrong address, here is the right one! ;-))
www.lowther.nl/oris-pictures.html
Regards,
Bert,
- ------
E-mail:
Business : BD-Design@lowther.nl
Private : BD@lowther.nl
Lowther Club Holland : LCH@lowther.nl
Homepage : http://www.lowther.nl
Tel./Fax: (0341) 254500 Mobile: (06) 51242990
=========================================================================
From: Peter Sikking <peter.sikking@virgin.net>
Subject: [JN] Finding parts in london...
Date: Thu, 03 May 2001 10:41:07 +0100
Source: Sound Digest Archive v02.n878
UK Joes,
are there any cheap/surplus electronic component stores here in london?
Not the big parts houses like RS, but places where they let you rummage
around and find a treasure between the junk?
Thanks,
--ps/031
=========================================================================
From: Thomas Danley <Tom@ppci.com>
Subject: [JN] Find out first hand
Date: Thu, 11 Feb 1999 10:31:53 -0600
Source: Sound Digest Archive v02.n041
- --------------F36EC83149D3C7A9ED57853C
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7bit
Hi
Back from a vacation and sorting through 500+ e-mails and found an
interesting one.
For those undecided about the validity of double blind testing (as applied
only to audio) or interested to find out what your own ears alone can tell
you, or to find an error in methodology and suggest improvements to make it
"more valid" consider going to this event.
Or if you are in the Chicago area and want to talk to other audio builders
and a number of "names" in the industry may want to go to this listening
challenge.
Hopefully they will not mind I posted this to the list
> PSACS will next meet at the home of Tom Perazella, 1295 Christopher Ct., Sleepy Hollow, IL on Febr
uary
> 20, 1999, 2 PM, Tom is host and cohost, $3 each if you want refreshments, blah, blah. 847-426-836
1.
> Aaaaaawll Rightee Then!
>
> Program: ABX test of crummy old op-amp vs. the latest and greatest,
> hi-tech DC to light wonder op-amp. Think you got golden ears? Come
> and show us!
>
> Demo: Tom Perazella will show his TP 8-12 custom multi-driver
> subwoofer system featured in January 99 Audio magazine. Come hear
> the real thing.
>
> Full details in the newsletter.
>
> Cool Web Sites:
> http://liftoff.msfc.nasa.gov/realtime/jtrack/3d/jtrack3d.html >>> Real-time satellite positions.
> http://www.7shades.com/ >>> New RTA for $99! You supply the mic and PC.
> http://members.tripod.com/nightstormer/audio.html >>> DIY Audio Page
> http://invalid.ed.unit.no/~dunker/horns.html >>> Horn loudspeakers.
> http://www.audio-x-stream.com/ >>> Rudi Blondia's web site - lotsa pictures and cool frequency re
sponse
> graphs. He has mucho info on ribbon drivers.
> http://www.pcavtech.com/index.htm >>> Arny Krueger's site, one of the inventors of the ABX box.
>
- --------------F36EC83149D3C7A9ED57853C
Content-Type: text/html; charset=us-ascii
Content-Transfer-Encoding: 7bit
<!doctype html public "-//w3c//dtd html 4.0 transitional//en">
<html>
Hi
<p>Back from a vacation and sorting through 500+ e-mails and found an interesting
one.
<br>For those undecided about the validity of double blind testing (as
applied only to audio) or interested to find out what your own ears alone
can tell you, or to find an error in methodology and suggest improvements
to make it "more valid" consider going to this event.
<br>Or if you are in the Chicago area and want to talk to other audio builders
and a number of "names" in the industry may want to go to this listening
challenge.
<br>Hopefully they will not mind I posted this to the list
<blockquote TYPE=CITE>
<pre>PSACS will next meet at the home of Tom Perazella, 1295 Christopher Ct., Sleepy Hollow, IL on F
ebruary
20, 1999, 2 PM, Tom is host and cohost, $3 each if you want refreshments, blah, blah. 847-426-
8361.
Aaaaaawll Rightee Then!
Program: ABX test of crummy old op-amp vs. the latest and greatest,
hi-tech DC to light wonder op-amp. Think you got golden ears? Come
and show us!
Demo: Tom Perazella will show his TP 8-12 custom multi-driver
subwoofer system featured in January 99 Audio magazine. Come hear
the real thing.
Full details in the newsletter.
Cool Web Sites:
<A HREF="http://liftoff.msfc.nasa.gov/realtime/jtrack/3d/jtrack3d.html">http://liftoff.msfc.nasa.gov
/realtime/jtrack/3d/jtrack3d.html</A> >>> Real-time satellite positions.
<A HREF="http://www.7shades.com/">http://www.7shades.com/</A> >>> New RTA for $99! You supply
the mic and PC.
<A HREF="http://members.tripod.com/nightstormer/audio.html">http://members.tripod.com/nightstormer/a
udio.html</A> >>> DIY Audio Page
<A HREF="http://invalid.ed.unit.no/~dunker/horns.html">http://invalid.ed.unit.no/~dunker/horns.html<
/A> >>> Horn loudspeakers.
<A HREF="http://www.audio-x-stream.com/">http://www.audio-x-stream.com/</A> >>> Rudi Blondia's
web site - lotsa pictures and cool frequency response
graphs. He has mucho info on ribbon drivers.
<A HREF="http://www.pcavtech.com/index.htm">http://www.pcavtech.com/index.htm</A> >>> Ar
ny Krueger's site, one of the inventors of the ABX box.</pre>
</blockquote>
<br>
<br> </html>
- --------------F36EC83149D3C7A9ED57853C--
=========================================================================
From: "Mindaugas K." <mk@is.lt>
Subject: [JN] Fine tuning of tube amp
Date: Mon, 08 Feb 1999 23:36:32 +0100
Source: Sound Digest Archive v02.n034
Hi.
Once the amp is built, I suppose I need to tune it to the maximum. Maybe
you can suggest some fine tuning tips or provide some references. Please do
not laugh, but I hardly know where to start... I have a professional scope,
low freq generator, and high precision multimeter available to me.
Thanks in advance.
Mindaugas
mk@is.lt
=========================================================================
From: "Carter Hendricks" <carter@i1.net>
Subject: [JN] Fine wine.
Date: Sun, 2 Jan 2000 23:38:43 -0600
Source: Sound Digest Archive v02.n381
I spent this afternoon listening to the new
Dynavector XV-something cartridge. I'm
not at all prepared to compare cartridges
which, well, cost so much money. Crazy
money. But I can say that it is from another
world.
The spoken intent of the designer is to respond
to the latest wave of expensive and competent
CD players. I like expensive CD players.
The cartridge is powerful and dynamic. The music
appears to have no source. It plays everything so
well; we listened to Sonny Rollins and to Ellington
and to Starker... Piano, sax, cello, bass, percussion.
I've never heard recorded music like this. Music.
Not hi fi. Just music.
The Rollins record was exciting, like listening from
the front row to my old friend JD Parran. The Starker
was, well, riveting.
The Starker record was an old scratchy copy that
Pranka* had found at Gene's. The cartridge
brought out all of Starker [noisy guy] and his
Cello. Cheap records are no problem. But
building a "system" equal to this source just
might be difficult.
I learned something about cartridges today.
[Including that I like the good ones]. I enjoyed
a lot of music. And I was reminded that the
top shelf is a long ways up.
--Carter
- -----------
* disclaimer:
I heard the cartridge at Pranka's house.
He's trying to put a few hours on it before
it leaves tomorrow for CES. Pranka
imports these things, and I fix his [fast]
Alfa. We're friends. And no one from this
list is going to buy one of these things!!
=========================================================================
From: David Barnett <d_n_b@swbell.net>
Subject: Re: [JN] Finished building the Shindo Claret Preamp Copy now - very nice sound
Date: Mon, 29 May 2000 15:55:49 -0500
Source: Sound Digest Archive v02.n559
On Mon, 29 May 2000 18:57:58 +0000 (GMT), "T. Loesch"
<ezee_e@hotmail.com> wrote:
>For those interested in the Design, there is very little unusual about this
>Pre, however the basic design seems exceedingly well thought out.
Is the schematic posted anywhere?
- --dnb
=========================================================================
From: "T. Loesch" <ezee_e@hotmail.com>
Subject: [JN] Finished building the Shindo Claret Preamp Copy now - very nice sound
Date: Mon, 29 May 2000 18:57:58 GMT
Source: Sound Digest Archive v02.n559
Hi Folks,
I have finally finished off this long dragging Project. And I'm rather
pleased with the results. The Claret copy, while not able to match my
"reference", the modified Arthur Loesch Preamp (called Toccata) for
transparency and detail comes close enough for me not feel any major loss.
On the other hand I really like the "tone" of this preamp. The sound is
smooth, silky with a nice strong and gutsy bass. Overall the sound is what a
Friend once described as "sounding expensive". For me the pre sounds perhaps
ever so slightly too nice, but I have more then enough records and CD's that
benefit tremendously from the "nice" treatment.
For those interested in the Design, there is very little unusual about this
Pre, however the basic design seems exceedingly well thought out.
The Phonostage is MM only, mostly the classic dual ECC83 with negative
Feedback Equaliser. The main difference here is that both ECC83's operate
with much lower Anode Load Resistors than common and the second stage
operates at much more current than common with only 22kOhm Anode load, the
second cathode Resistor is 500 ohm and bypassed.
This gives much more current to drive the RIAA Network which in
addition is very high Impedance, thus avoiding the "gray" colorations so
often found with the ECC83 feedback circuits, which are due to the second
stage slewing into the Capacitance of the RIAA Network. The RIAA Network is
not strictly according to the RIAA Timeconstants at LF, this is explained by
the much lower gain of the two stages (due to the low value Anode Resistors)
that neccesitates a different EQ to get the LF range right.
The Linestage uses a 500k LINEAR LAW Volume Control which together with the
680k Feedback resistor from the Output of the Linestage gives an almost
logarithmic law behaviour of the Linestage as the VC also changes the
linestage Gain.
The Linestage itself uses dual ECC81 or 12AY7/6072 (I used the latter) with
one Valve as simple Amplifier, cathode bypassed and with 100k Anode Load.
The second Valve operates as RC Coupled Cathode Follower, or more precisely
"bootstrap" Cathode follower, normally at 6.6mA and with a Load of 7k5 in
the Cathode.
The PSU uses a EZ80/80 Rectifier with an old Parmeko oilfilled Mains
Transformer. The Transformer delivers 230V-0V-230V at 100mA DC and 6.3V 4A.
It operates into a 22uF Reservoir Capacitor which is followed by three
1k/22uF RC Filter Cells, one more 1k/22uF Filter splits the PSU off to each
Linestage where it is about 250V. More Filters (22k/22uF and 150k/22uF
respectively in cascade for the 2nd and 1st PhonoStage per channel) feed the
Phonostage. The HT is absolutely clean, nothing I can see of mains noise
comes though.
The Capacitors used where (in keeping with Ken Shindos approach) not my
usual Ansar Polypropylen but cheap and cheerfull Nichicon VX Series Axial
Units (the same Sakuma San uses routinely). The 1K Resistors where generic,
low magnetic vitrious enamel wirewounds, the others Metal Film.
The LT is generated from the 6.3V 4A Heaterwinding which also feeds the
Rectifier Valve with AC. I used a Voltage Doubler with 4,700uF
Capacitors and then a 3.3 Ohm 10W Resistor as Filter into another 4,700uF
Capacitor.
The Resistor is in the negative leg of the Circuit and the direct negative
Voltage is hard grounded, thus elevating the Heaters 4V above Signalground
without resorting to additional Voltage Dividers and at a very low
Impedance. This is needed to reverse-bias the Heater/Cathode Diode which
otherwise can result in additional distortion. A 0.33 Ohm Resistor (5W) in
the connection from Transformer to the Rectifier is used to adjust the final
heatervoltage and as "currentbrake" to reduce the peak current in the
heaterwinding.
In my realisation I used a Carbon Pot for the Volume Control, fitted two
switched Phono-Inputs and switched for all but one line Input both Ground
and Signal, these Inputs are mostly for less critical AV Gear.
The Coupling Capacitors are all Arcotronics "KP72" Series Foil & Film types
(I rate these about Level with Hoveland Musicaps) in 1000V and all cathode
Bypass Capacitors are Elna Cerafine.
Most resistors are a specific type of no-name Metalfilms (from Maplin UK -
only their "M" Code Resistors need to be used - other generic Metalfilms
sound very different and much worse) which sound to my ears and those of
many of friends much like Holco's but with slightly more "detail" and
"bite".
Finally, I currently use Mullard EZ81 as Rectifier, Mullard CV4004 Single
Seam Anode in the Phonostage and Mullard CV4004 Box Anode in the second
stage. The Linestage uses an RCA 12AY7 (Black Anode) for the Amplifier, the
second of these at hand had a failed Heater in one halve so a Jan GE 6072A
***** operates in the Cathode Follower for now.
All in all I have been very surprised by this Preamp as it uses several of
my favourite Gripes (ECC83's in the Phonostage and with NFB, this very
rarely sounds anything but very foggy) and Cathode Followers in the
Linestage (even though I reduce my objections in the context of the CF being
within a Negative Feedback loop - still CF's tend to
generalise while at the same time sounding rather agressive).
Indeed, this preamp has all of the features I consider usually to be
sonically WRONG with Vintage Equipment and yet manages to sound great. It
has just enough of the Tubyness left to make for
slightly "rosetinted" view of things, but not enough to cause major
colorations.
Basically, it retains all of what I have often liked about better Vintage
Preamps (this "golden glow", this smoothness just like expensive Swiss or
Belgian chocolate - not the Cadburies crap they push on the people here in
the UK) without the compromised transparency and detail, the less that ideal
noiselevels, the weaknesses at the
frequency extremes so common with Vintage Pre's.
Indeed this Pre has some of the best bass I ever heard from a Pre, better
than my "reference" preamp. The treble is not as open and airy as the
modified Arthur Loesch Pre, but it comes quite close. I have on order a 500K
linear law tandem cermet pot from Vishay/Sfernice which might be able to
solve this too.
So, I'll eat some humble pie here, I could never get such good sound out of
ECC83's and Cathode Followers and all, but Ken Shindo did it. As usual, it's
not what you, it's how you do it that matters.
This Preamp will stick around my place, if not as the main Preamp certainly
as backup Pre. At the Moment I have no urge to put
the "Toccata" back into the system and the Shindo Pre is still breaking in
and getting better.
BTW, as MC Stepups I use at the moment a pair of antique (1950's) Ribbon
Microphone Stepup Transformers from an old Grampian Console Amp I bought
supposedly broken for a tenner. It also had basically unused GEC KT66 (pair)
in it as well as the Box Anode ECC83.... Nice buy I must say.
Poweramp is still the 300B SE Job (Fugue/Legacy 300B) with the EL84 Pethode
Driver and Valve regged PSU's, very similar to the older JC Verdier unit. At
the moment I'm running 2A3 Outputs as these sound better with the Speakers
(Hoerning Perikles) I'm testing at the moment for Enjoythemusic.com,
normally I like 300B's better, but these
Speakers are rather laid back.
I have on my shelf two pairs of Siemens C3m which I intend to use as new
Input/Driver Valves as soon as I get used to the system as it is now. These
should be very nice in the Poweramp. Looking at the curves and doing some
Math these look as if they could produce an even more Ideal Harmonic
Spectrum than the EL84's together with the 300B.
The only problems are the 20V heaters and the Loctal sockets (I have the
sockets luckily enough) which will require quite some mechanical changes.
Electrically they will drop in for the EL84 with only the Cathode Resistor
to change.
Okay, enough from me, I just thought some of this may be of interrest.
Ciao Thorsten
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From: Allen Wright <AllenVSE@compuserve.com>
Subject: [JN] Finished building the Shindo Claret Preamp Copy now - very nice sound
Date: Tue, 30 May 2000 03:13:18 -0400
Source: Sound Digest Archive v02.n559
Thorsten writes,
>>> I have on order a 500K linear law tandem cermet pot
from Vishay/Sfernice which might be able to solve this too<<<
Very interested in this pot - as you know I feel it's some 10x too high but
per your report, the Shindo breaks a lot of other rules as well.
The cermet Sfernice pots have a number of enthusiast users saying they are
sonically the best of anything (RATA etc) - but they also have gained a rep
for lasting one year - max! I'll be really interested in yor exoerience.
Also interested in knowing how long they take to deliver...
I have dispensed with conventional pots in my differential preamps - am now
using a single common mode gain changing (switched) resistor between the
line stage input tube's cathodes - with nothing in the main signal path.
KISS!
On the SuperReg front - I now have the +5 version down from 175milliohms to
5.6 milliohms OPZ at up to 100K! With a steady 6dB/octave worsening from
there following the opamps open loop rolloff.
This performance level should be transferrable to a +/- 15V design for all
SS applications and I have a inovative idea for a HV SuperReg using the
same chip which should provide similar bandwidth - but not yet tested.
The AD811 is quite a device...seems perfectly stable if you follow the
application note rules, but it immediately puts out RF that even my 100MHz
hp scope can't lock to if you do something off limits!
Allen (VSE)
=========================================================================
From: David Crittle <retrovox@bigpond.com>
Subject: [JN] Finished building the Shindo Claret Preamp Copy now - very nice sound
Date: Tue, 30 May 2000 09:41:29 +1000
Source: Sound Digest Archive v02.n559
>From: "T. Loesch" <ezee_e@hotmail.com>
<<snipz>>
>Finally, I currently use Mullard EZ81 as Rectifier, Mullard CV4004 Single
>Seam Anode in the Phonostage and Mullard CV4004 Box Anode in the second
>stage.
Thanks for the update Thorsten.
One obscure point: Is there such a thing as a Mullard CV4004 Single Seam
Anode? I thought the single seam CV4004 was made by Brimar, and the CV4004
Box Anode was made by Mullard. See a pic of both side by side at:
http://albums.photopoint.com/j/ViewPhoto?u=149682&a=1102709&p=13824474
(Reference pic only, I have nil stock these items)
David Crittle
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(Dr Seuess)
=========================================================================
From: "T. Loesch" <ezee_e@hotmail.com>
Subject: Re: [JN] Finished building the Shindo Claret Preamp Copy now - very nice sound
Date: Tue, 30 May 2000 09:49:25 GMT
Source: Sound Digest Archive v02.n559
Allan,
>Very interested in this pot - as you know I feel it's some 10x too high but
>per your report, the Shindo breaks a lot of other rules as well.
Actually, the 500k Linear law pot is essentially "Law-Faked" via the
feedback loop of the Linestage. So in this case the 500k is fine, otherwise
I'd usually agree with you.
>Also interested in knowing how long they take to deliver...
Well, mine will come from Audiocom UK (www.audiocom-uk.com) who will deliver
the more generic units quickly, it's the 500k linear law that's throwing
them off....
>The AD811 is quite a device...seems perfectly stable if you follow the
>application note rules, but it immediately puts out RF that even my 100MHz
>hp scope can't lock to if you do something off limits!
Yes, it's quite a primadonna, but worth bothering with if you must use "The
SS"....
Later T
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From: "T. Loesch" <ezee_e@hotmail.com>
Subject: Re: [JN] Finished building the Shindo Claret Preamp Copy now - very nice sound
Date: Tue, 30 May 2000 11:19:34 GMT
Source: Sound Digest Archive v02.n559
Hi there,
>Is the schematic posted anywhere?
As usual, X-Drive is the word....
Look for "Thorstens collected oddities" in Schematics.... There are two
unmarked resistors in the Phonostage, see the text of the message for
values.
Later T
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=========================================================================
From: "Miroslav Kubala" <mikubala@swissonline.ch>
Subject: [JN] finished painting
Date: Sun, 3 Dec 2000 23:57:34 +0100
Source: Sound Digest Archive v02.n750
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hi
at last I finished the pictures for exhibition
try please:
http://homepage.swissonline.ch/mirko-kubala/
have a good time
mirko
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<DIV><FONT face=3DArial size=3D2>hi</FONT></DIV>
<DIV><FONT face=3DArial size=3D2>at last I finished the pictures for=20
exhibition</FONT></DIV>
<DIV><FONT face=3DArial size=3D2>try please:</FONT></DIV>
<DIV><FONT face=3DArial size=3D2></FONT> </DIV>
<DIV><FONT face=3DArial size=3D2><A=20
href=3D"http://homepage.swissonline.ch/mirko-kubala/">http://homepage.swi=
ssonline.ch/mirko-kubala/</A></FONT></DIV>
<DIV><FONT face=3DArial size=3D2></FONT> </DIV>
<DIV><FONT face=3DArial size=3D2>have a good time</FONT></DIV>
<DIV><FONT face=3DArial size=3D2>mirko</FONT></DIV></BODY></HTML>
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=========================================================================
From: Robert C Chambers <rchamber@norwich.edu>
Subject: Re: [JN] finished painting
Date: Thu, 7 Dec 2000 14:08:31 -0500 (EST)
Source: Sound Digest Archive v02.n755
Good Show Mirko!
What Fun! But,I wish I could have attended your *opening reception*!
I especially like the "Stuhl". Also, some of the boobs are okay!
I am suprized you do not paint some valves in the *heated* condition! Or
did I miss them?
Best Wishes with your Exhibit!
Kind Regards,
Robert
On Sun, 3 Dec 2000, Miroslav Kubala wrote:
> hi
> at last I finished the pictures for exhibition
> try please:
>
> http://homepage.swissonline.ch/mirko-kubala/
>
> have a good time
> mirko
>
=========================================================================
From: "Sylvain Giguere" <pagebleu@globetrotter.qc.ca>
Subject: [JN] Fi primer 300B
Date: Fri, 7 Jan 2000 22:10:35 -0500
Source: Sound Digest Archive v02.n391
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Hi guys,
Ok, up to now I've built a Kit One (that I liked) then a version of the =
JE Lab 300se based on the VV30B that was.. . well, yukky, then the =
Shishido 2A3 that I am still enjoying living with, but here is the time =
for my next try. Just for the fun of it, I am recycling the JE 300 amp =
that lies around into the Fi brochure 300B project.
Reading the diagram I don't see any voltage indication when it comes at =
the B+ applied on the 300B. What would it be? 425V? any help would be =
apreciated here.
Thanks,
Sylvain
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