Sound Practices Mailing List Files - Volume 2
=========================================================================
From: John Niven <jn@cypress.com>
Subject: [JN] Re: "Wacky wood" and one liners asshole...
Date: Fri, 04 Feb 2000 11:45:53 -0800
Source: Sound Digest Archive v02.n434
Allen Wright wrote:
> 3/ Send ***ONLY*** txt messages to the list - turn off all the fancy
> options that double or triple the message count.
Woops!
I just checked my email settings which was set to editing in HTML. I
think this means that, provided the list can receive HTML, I don't get a
warning and the option of sending it as text only. So appended it again,
in case anyone missed it.
- --------------------------------------------------------------------------
James,
What's "whacky wood"? I'm currently cogitating a back-loaded horn and
struggling with my rusty geometry, and the problem of making the
structure
buildable with basic woodworking skills.
For a large horn, I'm assuming plywood is a better choice than mdf,
since
it has greater strength. My basic layout requires 3 one dimensional
curves, and I would prefer do do these with smooth curves than piecewise
approximations. I was wondering if I could use sheet Aluminum, but
whacky
wood sounds interesting :-)
Three more questions:-
1) Most designs I've seen start with a "parallel sides" assumption
(Hedlund horn included). This is presumably for simplicity. Is there any
sonic benefit in using flat sides but angled in a Vee shape? This would
conform better to the theoretical expansion.
2) Why do you recommend Exponential, or Hyperbolic contours over
Tractrix?
3) For a back-loaded bass horn, is a square or a rectangle mouth
preferred?
The Hedlund has tall narrow mouth. Presumably dictated by the parallel
sides? Does this help imaging?
Actually that was more than three questions, and the more I think the
more
I come up with :-)
Any advice would be appreciated,
John
James Melhuish wrote:
> site. Or you could design your own. You could use bending plywood
> (whacky wood) between two sheets of plywood or MDF and create a smooth
> curve. Use an exponential or hyperbolic contour with m=0.6 or 0.8, you
- -
_\|/
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: "Sylvain Giguere" <pagebleu@globetrotter.qc.ca>
Subject: [JN] Walking rollies...
Date: Sun, 11 Apr 1999 21:24:11 -0400
Source: Sound Digest Archive v02.n120
Christian says...
<<...and when you bend the leads of a rollie, it becomes a walkie...>>
Well... I'd bet we can find another trick to identify a rollie from a
walkie... hum, say the rollie is laying flat on the table with its legs wide
spread (blush..) in strait line with the body of the cap. Then, you have a
strait line, right? like an.. "axle"? then, may be we could name it.. Axial?
:)
Bad me.
Sylvain <s>
=========================================================================
From: Roscoe Primrose <roscoe@aiko.com>
Subject: Re: [JN] Walkman Pro
Date: Mon, 15 Feb 1999 18:35:25 -0500
Source: Sound Digest Archive v02.n045
I'd probably go with the D5, it's more robust and has better heads...
Peace
Ian McPhail wrote:
>
> Joefolks, the Sony Walkman Pro WM D6 was (still in production) a
> classic, beautifully built, excellent performance and ultra reliable.
> Would you still buy one today? The alternative being one of the
> plethora of portable MiniDisc recorders available today. Most of
> them appear to be built to the lowest cost and throwaway items if
> any breakdowns occur. Also the jury is divided on their dubious
> digital superiority.
> The Walkman Pro (well, we can't all afford a Nagra) appeals to me
> as deliciously retro (already?) analog, high performance, made of
> metal and built to the highest standards.
> 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
> fax +61 3 9925 3746
- --
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: JE <je2a3@erols.com>
Subject: Re: [JN] Walkman Pro
Date: Mon, 15 Feb 1999 19:12:44 -0800
Source: Sound Digest Archive v02.n045
Roscoe Primrose wrote:
> I'd probably go with the D5, it's more robust and has better heads...
I have to agree with this statement and add that the TCD5M has RCA line
in/out jacks and 1/4" mic inputs instead of the miniature jacks on the
WMD6C. It sounds better too.
I use/own both decks and for live recording, the TCD5M sees duty 95% of the
time and after 14 years, it's still going strong.
Regards,
Joseph
=========================================================================
From: "pagebleu" <pagebleu@globetrotter.qc.ca>
Subject: [JN] Walkman Pro
Date: Mon, 15 Feb 1999 22:48:26 -0500
Source: Sound Digest Archive v02.n045
This is a multi-part message in MIME format.
- ------=_NextPart_000_0051_01BE5935.4C685FC0
Content-Type: text/plain;
charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable
Ian, yes, the DM6 is sure a "classic". Nicely styled and solidly built =
as well as good sounding it seems. I agree that the minidiscs may be =
cheapo-built, but there are alternatives between them and the Nagras.. =
<s> I think.
I own a nice little TCD-D8 portable dat (yes, I hear you say digitis..) =
but the build quality is impressive, it is reliable, and honnestly =
(shame on me..) I almost can't tell the difference between a cd being =
played on my Meridian and a dat copy replayed on my D8... (shame on =
me...) Bastien Bouchard (here on the list) and I, have made some =
listening tests on his sound projects between the minidisc copy vs cd =
recorded sound takes... gee... would I like to say the minidisc was =
bad.. it wasn't. Just some slight hardening on the edges and here again, =
it was very subtle and discutable...
So, there might be hope for the empty wallet (like mine:) and the ones =
who look for a cheap way to realise decent recordings on the go. I sure =
look forward to the Montreal International Jazz Festival, next july...
Sylvain Gigu=E8re
- ------=_NextPart_000_0051_01BE5935.4C685FC0
Content-Type: text/html;
charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable
<!DOCTYPE HTML PUBLIC "-//W3C//DTD W3 HTML//EN">
<HTML><HEAD>
<META content=3Dtext/html;charset=3Diso-8859-1 =
http-equiv=3DContent-Type>
<STYLE></STYLE>
<META content=3D'"MSHTML 5.00.0910.1309"' name=3DGENERATOR></HEAD>
<BODY bgColor=3D#ffffff>
<DIV>Ian, yes, the DM6 is sure a "classic". Nicely styled and =
solidly=20
built as well as good sounding it seems. I agree that the minidiscs may =
be=20
cheapo-built, but there are alternatives between them and the Nagras.. =
<s>=20
I think.</DIV>
<DIV> </DIV>
<DIV>I own a nice little TCD-D8 portable dat (yes, I hear you say =
digitis..) but=20
the build quality is impressive, it is reliable, and honnestly (shame on =
me..) I=20
almost can't tell the difference between a cd being played on my =
Meridian and a=20
dat copy replayed on my D8... (shame on me...) Bastien Bouchard (here on =
the=20
list) and I, have made some listening tests on his sound projects =
between the=20
minidisc copy vs cd recorded sound takes... gee... would I like to say =
the=20
minidisc was bad.. it wasn't. Just some slight hardening on the edges =
and here=20
again, it was very subtle and discutable...</DIV>
<DIV> </DIV>
<DIV>So, there might be hope for the empty wallet (like mine:) and the =
ones who=20
look for a cheap way to realise decent recordings on the go. I sure look =
forward=20
to the Montreal International Jazz Festival, next july...</DIV>
<DIV> </DIV>
<DIV>Sylvain Gigu=E8re</DIV></BODY></HTML>
- ------=_NextPart_000_0051_01BE5935.4C685FC0--
=========================================================================
From: "Ian McPhail" <i.mcphail@rmit.EDU.AU>
Subject: [JN] Walkman Pro
Date: Tue, 16 Feb 1999 09:53:44 +1000
Source: Sound Digest Archive v02.n045
Joefolks, the Sony Walkman Pro WM D6 was (still in production) a
classic, beautifully built, excellent performance and ultra reliable.
Would you still buy one today? The alternative being one of the
plethora of portable MiniDisc recorders available today. Most of
them appear to be built to the lowest cost and throwaway items if
any breakdowns occur. Also the jury is divided on their dubious
digital superiority.
The Walkman Pro (well, we can't all afford a Nagra) appeals to me
as deliciously retro (already?) analog, high performance, made of
metal and built to the highest standards.
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
fax +61 3 9925 3746
=========================================================================
From: "Ian McPhail" <i.mcphail@rmit.EDU.AU>
Subject: [JN] re: Walkman Pro, TCD5M
Date: Tue, 16 Feb 1999 11:49:14 +1000
Source: Sound Digest Archive v02.n045
Joefolks, thanks for the reponse. Someone mentioned the TCD5M,
I can't find any reference to this model on the Sony site.
Any Clues?
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
fax +61 3 9925 3746
=========================================================================
From: "PEARL Cust Serv" <custserv@pearl-hifi.com>
Subject: [JN] Wall Socket War Stories was: Part 5 Shunt Regulators
Date: Mon, 13 Mar 2000 18:10:34 -0700
Source: Sound Digest Archive v02.n482
Hi Chris, All:
Hey, I have a story like that, two actually.
The first is along the lines of, "Boy Genius Strikes Again." One day
after school, at the age of about 8 or 9, I watched one those science shows
they aired live back in the 50s. That particular day the construction
project was a simple little electric motor that was intended to run on one
of those great big 1.5V dry cells, the ones with the cute little brass,
screw-down connections on top. That looked like the neatest thing so I built
one the next day after school - BUT - I had no battery to run it with - SO -
I just plugged it in . . . . I was in my sock feet on the basement floor, so
it's far more by good luck than good management that you have to put up with
me :>)
The second is rather more of the, " . . . . don't assume nuttin' "
variety and took place about 5 years later.
I used to repeatedly sign out a book from the library on "Electronics
for Children" or something like that . . . . I don't really recall the title
but I surely remember the author, "Harry Zarchy." I damned near did myself
in with one of his tube amp circuits . . . a circuit from which he'd omitted
the output transformer (NOW you know why I'm interested in these things.)
I certainly was not about to second guess the author of a *library book*
so I just built the amp, two of them actually, - line powered actually - and
put one of them in a box with my bedside regenerative AM radio to gain it up
to run a speaker.
Between a flourescent desk lamp with a previously undetected ground
fault and my having plugged the radio/amp to wrong way to, I managed one
night while DX-ing in the dark to light myself up by trying to turn on the
lamp while holding the metal, vernier tuning dial in the other hand. I took
120VAC + 300VDC straight across the thorax . . . . I ached for a week . . .
Now let me tell ya about my first girlfriend . . . . LOL
Bill - PEARL, Inc.
=====================
Chris Beck EuropaChris@netscape.net wrote:
> I think I was about the same age when I half-way unplugged the nightlight in
> my room and thought I'd hang the metal chain collar of a stuffed dog over the
> plug prongs (stuffed dog not in the collar - I'm a geek, not a sadist...).
> WOW, did the fire fly! Turned the socket black, blew the breaker, and gave me
> numb arms for a few hours. Lucky I didn't kill myself.
>
> Chris
>
>
> SBench@aol.com wrote:
>
>> A little history. When I was 3 I stuck a bobby pin (remember those?)
>> into a wall outlet. Changed my future ;-)
>> Didn't do the wall outlet much good though, according to my parents.
>> I still remember the incident, but don't remember the thought process of
>> why I thought that might be a good thing to do 8-]
>>
>>
>> Best Regards,
>> Steve
>
>
> ____________________________________________________________________
> Get your own FREE, personal Netscape WebMail account today at
> http://webmail.netscape.com.
=========================================================================
From: "J. Gordon Rankin" <waudio@cinti.net>
Subject: [JN] Wall Wart supply boxes???
Date: Thu, 21 Sep 00 16:12:17 -0400
Source: Sound Digest Archive v02.n668
Gang,
Has any one seen these things. They are the plastic enclosures that are
used for making WALL Wart type supplies. Jameco use to have them in two
sizes. They actually have the two or three prongs built into them.
Any help would be appreciated!
Gordon
=====> Wavelength Audio <=====
mailto:waudio@cinti.net
mailto:wavelength@fuse.net
http://www.WavelengthAudio.com
ph.fx. 513-271-4186 USA
=========================================================================
From: Rick Francis <rfrancis@glasscity.net>
Subject: [JN] Wanted: 2" punch for defib caps
Date: Thu, 14 Dec 2000 20:28:32 -0500
Source: Sound Digest Archive v02.n759
Anyone remember those 36uF caps that Doc Bottlehead sold a long time
ago? I mounted some from below the chassis with a 2 1/8" punch I got on
ebay, and it works fine, but a 2" punch is all that's needed. For the
current project I'd like to save a little metal. So by any chance, does
anyone have an extra Greenlee 2" they'd like to sell or swap for?
- --Rick
=========================================================================
From: bill gardner <wg44929@navix.net>
Subject: [JN] wanted 414 8B
Date: Sun, 11 Jul 1999 09:14:38 -0500
Source: Sound Digest Archive v02.n202
Greetings and Salutations : Would like to purchase a pair of Altec 414 8 B
woofers .
Thanks and best William Gardner
800 348 4539 week days
402 330 0774 fax
=========================================================================
From: William Gardner <wg44929@mail.navix.net>
Subject: [JN] wanted 414
Date: Sat, 25 Mar 2000 11:37:15 -0600
Source: Sound Digest Archive v02.n496
Hi Gang Members : I need one only - Altec 414 8-B or C , I have a single of
each , BUT if you have a pair don't be bashfull, I'll take a pair . Have
started yet another project ....... just what we all need , (>: right ?
A pair of Onken Petite boxs TIA and as always , appreciate your help .
Bill Gardner
=========================================================================
From: ALEXSCIFI@aol.com
Subject: Re: [JN] wanted 414
Date: Sat, 25 Mar 2000 15:50:58 EST
Source: Sound Digest Archive v02.n496
In a message dated 2000-03-25 12:49:08 PM Eastern Standard Time,
wg44929@mail.navix.net writes:
> Hi Gang Members : I need one only - Altec 414 8-B or C , I have a single of
> each , BUT if you have a pair don't be bashfull, I'll take a pair . Have
> started yet another project ....... just what we all need , (>: right ?
> A pair of Onken Petite boxs TIA and as always , appreciate your help .
> Bill Gardner
>
>
Hi Bill
May I ask what constitues a "mini Onken" enclosure?
Thanks
Alex
=========================================================================
From: "Kurt Th. Steffensen" <kurt-steffensen@teliamail.dk>
Subject: [JN] Wanted:5675 curves
Date: Mon, 13 Sep 1999 18:29:41 +0300
Source: Sound Digest Archive v02.n277
Dear all.
As some of you might know , I accidently lost a huge collection of
data-books etc. , some years ago.
One tube I found interesting , but never came to use is the 5675.
I have a bunch of these.
As far as I remember , it WAS suitable for audio , however , with relative low bias ,
low u , and not particual low Ri or high S , it was not really a candidate to anything in
particual.
Now , I think , I happens to need a tube , such as this , but would like to be sure , before
I waste a lot of time , examining its merits....
The curves , sure would help a lot here.
Does anyone has these at hand ?
If any of you need some data-sheets , please , do not hesitate to try me.
I have colllected , quite many books again , and these with the ones , I was lucky enough ,
not to loose , makes a good library.
Sincerely
- - Kurt Steffensen
=========================================================================
From: "Sikking, Peter" <peter.sikking@nomura.co.uk>
Subject: [JN] Wanted: A few good...
Date: Wed, 4 Oct 2000 18:30:28 +0100
Source: Sound Digest Archive v02.n686
Guys,
I'm looking for ceramic novar/magnoval (same thing, right?) sockets.
Actually, I would not mind buying 100 of them if somebody has them.
Just in case they come in flavours: I need the ones with a hole in the
middle for the tube tip.
Later,
--Peter
: music lover : ultra-fi builder : ui designer & developer : on drums...
: from:amsterdam@london.uk : +44 20 7521 1070 : facsimile +44 20 7521 3686
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=========================================================================
From: Peter Boser <pboser@yahoo.com>
Subject: Re: [JN] Wanted: A few good...
Date: Fri, 6 Oct 2000 07:56:26 -0700 (PDT)
Source: Sound Digest Archive v02.n688
Looks like Antique Electronic Supply has them for $5
each. Look here:
http://www.tubesandmore.com/
Pete
- --- Scott Walters <sfwalters@worldnet.att.net> wrote:
> Peter, I tried to send this yesterday but it
> didn't appear on the list so
> I'll try again. Check the Svetlana Web site. I
> believe they have a socket to
> meet your requirements. The number is SK509 I
> think. The only rub would be
> their price, these being new rather than used parts
> from the junk box or ham
> swap meet, expense may be a little higher than you
> had in mind if you really
> do intend to purchase 100 of them.
>
> Svetlana Tube Sockets
>
> "Peter Sikking " wrote:
>
> > Guys,
> >
> > I'm looking for ceramic novar/magnoval (same
> thing, right?) sockets.
> >
>
> This goes along with what I've always been told.
>
> Hope this helps.
>
> Scott
>
>
>
>
__________________________________________________
Do You Yahoo!?
Yahoo! Photos - 35mm Quality Prints, Now Get 15 Free!
http://photos.yahoo.com/
=========================================================================
From: Peter Boser <pboser@yahoo.com>
Subject: Re: [JN] Wanted: A few good...
Date: Fri, 6 Oct 2000 08:00:11 -0700 (PDT)
Source: Sound Digest Archive v02.n688
Looks like Antique Electronic Supply has them for $5
each. Look here:
http://www.tubesandmore.com/
Pete
- --- Scott Walters <sfwalters@worldnet.att.net> wrote:
> Peter, I tried to send this yesterday but it
> didn't appear on the list so
> I'll try again. Check the Svetlana Web site. I
> believe they have a socket to
> meet your requirements. The number is SK509 I
> think. The only rub would be
> their price, these being new rather than used parts
> from the junk box or ham
> swap meet, expense may be a little higher than you
> had in mind if you really
> do intend to purchase 100 of them.
>
> Svetlana Tube Sockets
>
> "Peter Sikking " wrote:
>
> > Guys,
> >
> > I'm looking for ceramic novar/magnoval (same
> thing, right?) sockets.
> >
>
> This goes along with what I've always been told.
>
> Hope this helps.
>
> Scott
>
>
>
>
__________________________________________________
Do You Yahoo!?
Yahoo! Photos - 35mm Quality Prints, Now Get 15 Free!
http://photos.yahoo.com/
=========================================================================
From: Peter Boser <pboser@yahoo.com>
Subject: Re: [JN] Wanted: A few good...
Date: Fri, 6 Oct 2000 08:01:13 -0700 (PDT)
Source: Sound Digest Archive v02.n688
Looks like Antique Electronic Supply has them for $5
each. Look here:
http://www.tubesandmore.com/
Pete
- --- Scott Walters <sfwalters@worldnet.att.net> wrote:
> Peter, I tried to send this yesterday but it
> didn't appear on the list so
> I'll try again. Check the Svetlana Web site. I
> believe they have a socket to
> meet your requirements. The number is SK509 I
> think. The only rub would be
> their price, these being new rather than used parts
> from the junk box or ham
> swap meet, expense may be a little higher than you
> had in mind if you really
> do intend to purchase 100 of them.
>
> Svetlana Tube Sockets
>
> "Peter Sikking " wrote:
>
> > Guys,
> >
> > I'm looking for ceramic novar/magnoval (same
> thing, right?) sockets.
> >
>
> This goes along with what I've always been told.
>
> Hope this helps.
>
> Scott
>
>
>
>
__________________________________________________
Do You Yahoo!?
Yahoo! Photos - 35mm Quality Prints, Now Get 15 Free!
http://photos.yahoo.com/
=========================================================================
From: Peter Boser <pboser@yahoo.com>
Subject: Re: [JN] Wanted: A few good...
Date: Fri, 6 Oct 2000 08:01:29 -0700 (PDT)
Source: Sound Digest Archive v02.n688
Looks like Antique Electronic Supply has them for $5
each. Look here:
http://www.tubesandmore.com/
Pete
- --- Scott Walters <sfwalters@worldnet.att.net> wrote:
> Peter, I tried to send this yesterday but it
> didn't appear on the list so
> I'll try again. Check the Svetlana Web site. I
> believe they have a socket to
> meet your requirements. The number is SK509 I
> think. The only rub would be
> their price, these being new rather than used parts
> from the junk box or ham
> swap meet, expense may be a little higher than you
> had in mind if you really
> do intend to purchase 100 of them.
>
> Svetlana Tube Sockets
>
> "Peter Sikking " wrote:
>
> > Guys,
> >
> > I'm looking for ceramic novar/magnoval (same
> thing, right?) sockets.
> >
>
> This goes along with what I've always been told.
>
> Hope this helps.
>
> Scott
>
>
>
>
__________________________________________________
Do You Yahoo!?
Yahoo! Photos - 35mm Quality Prints, Now Get 15 Free!
http://photos.yahoo.com/
=========================================================================
From: Peter Boser <pboser@yahoo.com>
Subject: Re: [JN] Wanted: A few good...
Date: Fri, 6 Oct 2000 08:03:12 -0700 (PDT)
Source: Sound Digest Archive v02.n688
Looks like Antique Electronic Supply has them for $5
each. Look here:
http://www.tubesandmore.com/
Pete
__________________________________________________
Do You Yahoo!?
Yahoo! Photos - 35mm Quality Prints, Now Get 15 Free!
http://photos.yahoo.com/
=========================================================================
From: Scott Walters <sfwalters@worldnet.att.net>
Subject: Re: [JN] Wanted: A few good...
Date: Fri, 06 Oct 2000 08:50:29 -0500
Source: Sound Digest Archive v02.n688
Peter, I tried to send this yesterday but it didn't appear on the list so
I'll try again. Check the Svetlana Web site. I believe they have a socket to
meet your requirements. The number is SK509 I think. The only rub would be
their price, these being new rather than used parts from the junk box or ham
swap meet, expense may be a little higher than you had in mind if you really
do intend to purchase 100 of them.
Svetlana Tube Sockets
"Peter Sikking " wrote:
> Guys,
>
> I'm looking for ceramic novar/magnoval (same thing, right?) sockets.
>
This goes along with what I've always been told.
Hope this helps.
Scott
=========================================================================
From: Scott Walters <sfwalters@worldnet.att.net>
Subject: Re: [JN] Wanted: A few good...
Date: Fri, 06 Oct 2000 09:10:35 -0500
Source: Sound Digest Archive v02.n688
I just can't get the hang of this html thing!
The url is: <http.www.svstlana.com/docs/tubeframe.html>
Scott
>
=========================================================================
From: David Dlugos <planet10@pinc.com>
Subject: Re: [JN] Wanted: A few good...
Date: Fri, 06 Oct 2000 09:40:14 -0700
Source: Sound Digest Archive v02.n688
fixed,
>The url is: <http://www.svstlana.com/docs/tubeframe.html>
___________________
The box said Windows 9x or better, so i bought a Macintosh
=========================================================================
From: David Dlugos <planet10@pinc.com>
Subject: Re: [JN] Wanted: A few good...
Date: Fri, 06 Oct 2000 09:42:22 -0700
Source: Sound Digest Archive v02.n688
try again,
forgot to check the spelling,
>The url is: <http://www.svetlana.com/docs/tubeframe.html>
___________________
The box said Windows 9x or better, so i bought a Macintosh
=========================================================================
From: "hopper chu" <achu@medcaminc.com>
Subject: RE: [JN] Wanted: A few good...
Date: Mon, 9 Oct 2000 11:03:22 -0700
Source: Sound Digest Archive v02.n689
Hi All,
Just a word of caution....
The socket made by Svetlana is different from the ones sold by the Antique
Ele. Supply. If I remember correctly from I own experiences, the holes in
the SK509 socket is a little bigger than ones in the AES. For example, 6CJ3
(with a bit thinner pins) will fit into AES socket nicely but will be a bit
loose in the SK509. E55L with a thicker pins will NOT fit into the AES ones
without the risk of breaking the tube base...
hopper
=========================================================================
From: Tom Ronan <tronan@enteract.com>
Subject: [JN] Wanted: Altec 414 drivers, and 802s
Date: Tue, 26 Oct 1999 04:12:44 +0000
Source: Sound Digest Archive v02.n315
Anyone out there have a pair of the 414 drivers for sale? They're the
Altec driver like the 416 but only 12". I'm also looking for a pair of 802
drivers or 806 drivers.
Please send private email with condition and price!
Thanks,
Tom
- ---------------------------------------------------------
Tom Ronan 1045 W. Montana Chicago, IL 60614
Lowther America http://www.lowther-america.com
26 Preamp & Oris 150 Horns http://www.enteract.com/~tronan
=========================================================================
From: Rimmer deVries <rdevries@ameritech.net>
Subject: Re: [JN] Wanted: Altec 802
Date: Sun, 31 Jan 1999 11:26:22 -0500
Source: Sound Digest Archive v02.n018
Hi All:
I need a nice pair of Altec 802 or 806 compression deivers, alnico,
Altec aluminum diaphragms, aluminum phase plugs.
If any of you have a pair for sale please let me know,
Regrds,
Rimmer deVries
=========================================================================
From: rcjones1@mmm.com
Subject: [JN] Wanted, and capacitor question.
Date: Thu, 7 Jun 2001 08:52:27 -0500
Source: Sound Digest Archive v02.n880
I am looking for a surplus 1KW isolation transformer. Any ideas?
Also, How are the Nichicon Muse capacitors for sound quality? I am looking
for some 200uf / 100v or so caps (40 total) which will be used in an output
stage. Anyone have any recommendations for caps? (I cannot afford to buy
40 BG!)
Thanks!
Richard Jones
=========================================================================
From: William Eckle <wmeckle@uswest.net>
Subject: Re: [JN]:Wanted: bass-reflex help.
Date: Wed, 09 Jun 1999 09:36:19 -0700
Source: Sound Digest Archive v02.n173
At 01:24 PM 6/9/99 +0200, Torbj=F8rn Lien wrote:
>Ok. Here is some driver spec's:
>
>JBL 2240 18" Bass unit:
>I want the box's f-low limit to be around 33-36Hz.
>No need to go deeper than that.=20
Hi Torbjorn:
Running the JBL 2240 through "Top Box", for minumum ripple (0) calls=
for a 98.7 liter vented box,
tuned to 43.5 Hz, with a -3 db point of 54.4 Hz and a sensitivity of 98.8=
db at 2.83v.
Sorry, looks like you need a true subwoofer driver.
<bold><color><param>ffff,0000,0000</param>-=3DBill Eckle=3D-
</color></bold>wmeckle@uswest.net
<italic><color><param>0000,0000,ffff</param>Phoenix, Arizona
USA</color></italic>
=========================================================================
From: "=?ISO-8859-1?Q?Torbj=F8rn_Lien?=" <mdrivekl@online.no>
Subject: [JN]:Wanted: bass-reflex help.
Date: Wed, 9 Jun 1999 13:24:09 +0200
Source: Sound Digest Archive v02.n173
Hello all.
In the old days I used to build all kinds of
speakers. It's been a while, but this summer
I hope to find time to make apair of dedicated
bass/PA boxes.
I've had limited success with bass-reflex speakers.
Earlier on I've made designs that were *thoroughly*
by the book,-meaning measuring out Thiele-Small
parameters on units, using Dickason's "The Loudspeaker coockbook" to
find alignments,-and make and tune
the box according to the receipt. And everything
the old fashioned way. A tiresome process!
The results were ok I suppose,-Today I feel they were limited by raw
driver quality.
Later on I've made afew nice cabs for bass-geetar,
just using a "that looks about right" principle.
(This ehm,-..thumb principle work rather well:
1: Make the box as large as possibly convenient.
2: Make the vent-area as large as possibly convenient.
3: Tune the duct-lenght to get
F-box resonnance equal to raw driver resonnance,-or
alittle higher....)
........
This time I'll make a pair of 18" cabs, using the
somewhat old JBL 2240's. And with a little more
scientific approach..
So I was thinking: Since there is all these
Loudspeaker-designing tools for PC about these days,-
Calsod or Leap or whatever they're all called,-
I bet/HOPE! someone on the list could just punch in
the values, and get out the cab-parameters for an
ok consept. (Would make me happy..)
Ok. Here is some driver spec's:
JBL 2240 18" Bass unit:
Diameter: 45,72cm.
Vas : 481,4 Litres
X-max : O,56 cm.
Z-nom : 8ohms
Re : 6ohms
Qm : 2,2
Qe : 0,25
Qts : 0,23
Fs : 30Hz
I want the box's f-low limit to be around 33-36Hz.
No need to go deeper than that.
The electrical Q of driver will probably be impaired
by around 0,5-0,8 ohm output resistanse from amp/cables.
The box's will be built of 3/4 birch-plywood. They will
ofcource be well braced with internal shelfs etc., so
that stiffness to lo-frequencies is,-"sufficient"...
I know the ability to handle transients , and lo
distortion,- all connects to cab-size...
Lets just say I want both a manageable cab size
and sound quality to balance...
Someone?!
TIA!
Regards
Torbjoern, Norway
=========================================================================
From: "Le Cleac'h J.-M." <lecleach@cgi.ensmp.fr>
Subject: Re: [JN]:Wanted: bass-reflex help.
Date: Wed, 9 Jun 1999 16:46:41 +0200
Source: Sound Digest Archive v02.n173
- ----------
> De : Torbjørn Lien <mdrivekl@online.no>
> A : sound@lists.io.com
> Objet : [JN]:Wanted: bass-reflex help.
> Date : mercredi 9 juin 1999 13:24
> So I was thinking: Since there is all these
> Loudspeaker-designing tools for PC about these days,-
> Calsod or Leap or whatever they're all called,-
> I bet/HOPE! someone on the list could just punch in
> the values, and get out the cab-parameters for an
> ok consept. (Would make me happy..)
>
> Ok. Here is some driver spec's:
>
> JBL 2240 18" Bass unit:
> Diameter: 45,72cm.
> Vas : 481,4 Litres
> X-max : O,56 cm.
> Z-nom : 8ohms
> Re : 6ohms
> Qm : 2,2
> Qe : 0,25
> Qts : 0,23
> Fs : 30Hz
>
> I want the box's f-low limit to be around 33-36Hz.
> No need to go deeper than that.
Hello,
I don't use such software but a simple spreadsheet to calculate the
response curve of conventionnal bass-reflex.
If you don't allow a bump more than 1dB at the tuning frequency, there is
no chance that in a conventionnal bass reflex the JBL 2240 will reach 35Hz.
The optimim bass reflex for the JBL2240 are 55 (alignment n = 5.7 giving a
127 liters box) to 65 Hz (alignment n = 4, giving a 89 liters box), the
last alignment is the best one for that loudspeaker IMHO but 65 Hz is not
specially deep bass.
Best regards,
Jean-Michel Le Cleac'h, Paris, France
=========================================================================
From: "=?ISO-8859-1?Q?Torbj=F8rn_Lien?=" <mdrivekl@online.no>
Subject: Re: [JN]:Wanted: bass-reflex help.
Date: Wed, 9 Jun 1999 17:47:51 +0200
Source: Sound Digest Archive v02.n173
Hello Jean Michel,
Thanks for looking into this.
I wrote:
> > So I was thinking: Since there is all these
> > Loudspeaker-designing tools for PC about these days,-
> > Calsod or Leap or whatever they're all called,-
> > I bet/HOPE! someone on the list could just punch in
> > the values, and get out the cab-parameters for an
> > ok consept. (Would make me happy..)
> >
> > Ok. Here is some driver spec's:
> >
> > JBL 2240 18" Bass unit:
> > Diameter: 45,72cm.
> > Vas : 481,4 Litres
> > X-max : O,56 cm.
> > Z-nom : 8ohms
> > Re : 6ohms
> > Qm : 2,2
> > Qe : 0,25
> > Qts : 0,23
> > Fs : 30Hz
> >
> > I want the box's f-low limit to be around 33-36Hz.
> > No need to go deeper than that.
>
Jean Michel wrote:
>
> I don't use such software but a simple spreadsheet
> to calculate the response curve of conventionnal
> bass-reflex.
>
> If you don't allow a bump more than 1dB at the tuning
> frequency, there is no chance that in a conventionnal bass > reflex
the JBL 2240 will reach 35Hz.
> The optimim bass reflex for the JBL2240 are 55
> (alignment n = 5.7 giving a 127 liters box) to 65 Hz > (alignment n =
4, giving a 89 liters box), the
> last alignment is the best one for that loudspeaker IMHO
> but 65 Hz is not specially deep bass.
>
UhHu! That doesn't look particularly promising regarding
*bass*. And I somehow have a feeling that both 127 and 90 liters is on
the small side for an 18"'er to breathe...
As I understand it a lower tuning/bigger box will
produce an uneven responce with first a premature rollof
and then a bump,-and you write that this is the result of the
"conventional bass-reflex" tuning..
Maybe the problem is the Qe? It could easily be destroyd
by an encreased output resistance.(The thing is planned
used with a variable-n.feedback tube amp.)
Could a drive resistance in the 4-8ohm area allow for
using a somewhat bigger box with lowered tuning?
I could also use more violent means and alter the units
parameters,-(But this is somewhat difficult to reverse.)
A wash-out and recoating of the surrounds together with
mild-destructive surgery to the spider could lover Fres..
Other wievs/sollutions to this?
TIA
Torbjoern, Norway
>
>
>
>
=========================================================================
From: WBamb83392@aol.com
Subject: Re: [JN]:Wanted: bass-reflex help.
Date: Wed, 9 Jun 1999 14:06:58 EDT
Source: Sound Digest Archive v02.n174
In a message dated 6/9/99 7:30:30 AM Eastern Daylight Time,
mdrivekl@online.no writes:
<< Ok. Here is some driver spec's:
JBL 2240 18" Bass unit:
Diameter: 45,72cm.
Vas : 481,4 Litres
X-max : O,56 cm.
Z-nom : 8ohms
Re : 6ohms
Qm : 2,2
Qe : 0,25
Qts : 0,23
Fs : 30Hz
I want the box's f-low limit to be around 33-36Hz.
No need to go deeper than that. >>
8-10 cubic feet tuned to 32Hz and you should be perfectly happy. I've
already built many such cabinets for 5 string (Low B) basses, and they work
fantastically. This alignment is called Extended Bass Shelf and is
incredibly useful. Bass guitars have a built in bass boost from the
increasing string length as one plays lower notes in addition to the
frequency response of typical pickups. This completely annuls the shallow
droop in the bass response from an EBS alignment. As long as the knee in the
frequency response coincides with the the pitch of the lowest note on the
bass, all is well. Outdoors, where there is no reinforcement of the bass, a
simple twist of the typical bass knob will give your EBS cabinet a flat
response. It's coincidence that typical bass boost controls flatten the
response of EBS alignments, but it's a handy coincidence. Indoors, the
response of the typicalroom flattens the response of an EBS enclosure.
- -Eric Bamberg
=========================================================================
From: "Daniel J. Marshall" <danmarshall@worldnet.att.net>
Subject: Re: [JN]:Wanted: bass-reflex help.
Date: Wed, 09 Jun 1999 14:11:38 -0700
Source: Sound Digest Archive v02.n174
WBamb83392@aol.com wrote:
>
> In a message dated 6/9/99 7:30:30 AM Eastern Daylight Time,
> mdrivekl@online.no writes:
>
> << Ok. Here is some driver spec's:
>
> JBL 2240 18" Bass unit:
> Diameter: 45,72cm.
> Vas : 481,4 Litres
> X-max : O,56 cm.
> Z-nom : 8ohms
> Re : 6ohms
> Qm : 2,2
> Qe : 0,25
> Qts : 0,23
> Fs : 30Hz
>
> I want the box's f-low limit to be around 33-36Hz.
> No need to go deeper than that. >>
>
> 8-10 cubic feet tuned to 32Hz and you should be perfectly happy. I've
> already built many such cabinets for 5 string (Low B) basses, and they work
> fantastically. This alignment is called Extended Bass Shelf and is
> incredibly useful. Bass guitars have a built in bass boost from the
> increasing string length as one plays lower notes in addition to the
> frequency response of typical pickups. This completely annuls the shallow
> droop in the bass response from an EBS alignment. As long as the knee in the
> frequency response coincides with the the pitch of the lowest note on the
> bass, all is well. Outdoors, where there is no reinforcement of the bass, a
> simple twist of the typical bass knob will give your EBS cabinet a flat
> response. It's coincidence that typical bass boost controls flatten the
> response of EBS alignments, but it's a handy coincidence. Indoors, the
> response of the typicalroom flattens the response of an EBS enclosure.
>
> -Eric Bamberg
Hi Torgjoern, Eric,
I have to vote with Eric on this one. JBL generally puts that speaker
in their 4518 enclosure which is 8 cu. ft. volume. Exterior dimensions
are (HxWxD): 1060mm x 667mm x 464mm (39 3/4" x 26 1/2" x 17 1/4") with
the speaker mounted well towards the bottom and with three round ducted
vents above the speaker (in a horizontal row). The vents look to be
about 3 1/2 to 4 inches, or so, in diameter. They claim usable
frequency to 30 Hz, but don't state the tuning frequency. However, I
suspect it most likely is in the low 30s, perhaps 30 Hz. I would assume
that JBL has pretty well thought out the details over the years, taking
portability factors into acount, as well, so I doubt that you would
improve a great deal on their design, esp since it is based on years of
experience. Oh, if you have special needs, then perhaps, but all things
considered, for general use, they probably have it pretty well thought
out.
After writing this, I plugged the parameters into my homebrew
spreadsheet that calculates freq resp from TS parameters. It plots the
frequency response for 8 integral values of Ql values from 4 through
11. This is something that seems to be glossed over most of the time,
as it is difficult (impossible) to predetermine. Taking an educated
guess seems as appropriate as anything else. I would like to emphasize
that Ql has a very profound effect on low bass performance and every
precaution should be taken to totally seal the enclossure (exc for the
port), including gasketing the woofer and to generously use cross
bracing to make the walls as rigid as possible. For portable use you
would want to use plywood for its lighter weight and substantially
greater strength. Just sitting a large MDS or particle board enclosure
down a bit too gingerly on its on corner hard pavement can cause the
entire corner to fracture, plus they are quite heavy to lug about.
When looking at the predicted freq resp, it doesn't look very inspiring,
as the rolloff at 30 Hz is significant, less for high Ql, but still
signficant. Of course room boost, as Eric points out, is not taken into
account, which will offset much of the rolloff. I would not alter the
speaker itself. If you want stronger low-end response, then add some
series resistance to raise the Qts (or drive it from a high Z tube amp)
and use a larger box. But then, boxes much larger than about 8 cu ft
are a pain in the whatzit to tote about. The form factor used by JBL
makes for a convenient size to move about on a two wheel dolly, or you
could permanently attached a pair of wheels and a handle for a built-in
two-wheel dolly.
If minimum size is the goal, the best approach would be to design a 6th
order system. It so happens that the optimum 6th order design turns out
to be with a Qts of 0.312 (add 2.1 ohms series res), volume = .4 x VAS =
6.8 cu. ft., box tuning = fs (30 Hz) with a 2nd order eq Q of 2. This
requires extra power at the boost freq, so a whompin great SS amp would
seem appropriate. You could then use, or bypass, the equalizer as
environment dictates. If you want flat response to 30 Hz, then adjust
the Qts to the optimum value of 0.383 (4 ohms series res), use a 17 cu
ft enclosure tuned to fs (30 Hz). If you can attain a Ql of 8 (which is
probably a higher value than you would achieve in practice), then it
would give flat response to 30 Hz. This might not work as well though,
as power handling would likely be compromised and room boost is not
taken into account which would probably result in over emphasizing the
low end and it may have flabby bass. This takes us back to where we
started, JBL probably has it pretty well optimized, all things
considered,, so I would go with their enclosure design. If you can beg,
borow or steal an enclosure this size for a trial run, it might save you
some wheel spinning.
Dan Marshall
=========================================================================
From: "=?ISO-8859-1?Q?Torbj=F8rn_Lien?=" <mdrivekl@online.no>
Subject: Re: [JN]:Wanted: bass-reflex help.
Date: Wed, 9 Jun 1999 19:51:59 +0200
Source: Sound Digest Archive v02.n174
Hello William.
Thanks for the reply, looks like your
conclusions is more or less in line
with the ones I got from Jean Michel.
(In the answer to that I wented the idea
of altering the unit's parameters.
What do you think of that?)
Do you/anybody have any knowledge to what
these units initially was used for?
Regards
Torbjoern, Norway
> Running the JBL 2240 through "Top Box", for minumum
> ripple (0) calls for a 98.7 liter vented box,
> tuned to 43.5 Hz, with a -3 db point of 54.4 Hz
> and a sensitivity of 98.8 db at 2.83v.
> Sorry, looks like you need a true subwoofer driver.
=========================================================================
From: "Farwell-Clay" <wclay@mediaone.net>
Subject: [JN] Wanted: Cardmatic Tube Tester Card for #10
Date: Tue, 26 Jun 2001 14:17:01 -0400
Source: Sound Digest Archive v02.n916
Hello everyone,
Does anyone have a spare Hickok 123 or 118 cardmatic card to test a #10
tube? Or a blank they could cut? Equivalents O.K. too. I'd of course
appreciate it greatly and pay whatever, etc.
Thanks!
Walter Clay
=========================================================================
From: bill gardner <wg44929@navix.net>
Subject: [JN] wanted dead or alive
Date: Tue, 30 Mar 1999 20:29:52 -0600
Source: Sound Digest Archive v02.n102
joes and ms Logg : Would like to buy Altec 1520 or 1530 amps , singles
pairs , trannys etc ..... any for sale?
Thanks and best as always William
Gardner
=========================================================================
From: "Raymond van Weeghel" <raymondvanweeghel@hotmail.com>
Subject: Re: [JN] Wanted dead or alive: BB PCM1702 datasheet
Date: Tue, 21 Aug 2001 11:23:04 +0200
Source: Sound Digest Archive v02.n951
http://www.audiocom-uk.com/Data_Sheets/PCM1702.pdf
have fun
Raymond
- ----- Original Message -----
From: "David Home" <David_Home@creoscitex.com>
To: "Remco Stoutjesdijk" <remco@ultranalog.com>; <sound@lists.io.com>
Sent: Tuesday, August 21, 2001 10:11 AM
Subject: RE: [JN] Wanted dead or alive: BB PCM1732 datasheet
> Can't find the datasheet for the PCM 1702 either.
> Anyone got it or point me to it?
> Regards, David
>
> -----Original Message-----
> From: Remco Stoutjesdijk [mailto:remco@ultranalog.com]
> Sent: Friday, August 17, 2001 9:59 PM
> To: sound@lists.io.com
> Subject: [JN] Wanted dead or alive: BB PCM1732 datasheet
>
>
> Gang,
>
> Longshot:
> Is there anybody out there who has this datasheet somewhere? It has been
> available for a while, but now Burr-Brown doesn't have it online anymore,
> probably since it's the world's first HDCD + DAC integrated chip. Looks
> interesting. I have an NAD player here that has it, but is infected with
> opamps and needs to be cured from this horrible disease.
> I have already figured out the topology and pinout but would like to know
> something more about the internal setup and just have the d**ned sheet...
>
> TIA,
>
> Remco
> --
> http://www.ultranalog.com
>
=========================================================================
From: Remco Stoutjesdijk <remco@ultranalog.com>
Subject: [JN] Wanted dead or alive: BB PCM1732 datasheet
Date: Fri, 17 Aug 2001 21:58:49 +0200
Source: Sound Digest Archive v02.n949
Gang,
Longshot:
Is there anybody out there who has this datasheet somewhere? It has been available for a while, but
now Burr-Brown doesn't have it online anymore, probably since it's the world's first HDCD + DAC inte
grated chip. Looks interesting. I have an NAD player here that has it, but is infected with opamps a
nd needs to be cured from this horrible disease.
I have already figured out the topology and pinout but would like to know something more about the i
nternal setup and just have the d**ned sheet...
TIA,
Remco
- --
http://www.ultranalog.com
=========================================================================
From: "Raymond van Weeghel" <raymondvanweeghel@hotmail.com>
Subject: Re: [JN] Wanted dead or alive: BB PCM1732 datasheet
Date: Sat, 18 Aug 2001 14:12:13 +0200
Source: Sound Digest Archive v02.n949
> Longshot:
> Is there anybody out there who has this datasheet somewhere? It has been
available for a while, but now Burr-Brown doesn't have it online anymore,
probably since it's the world's first HDCD + DAC integrated chip. Looks
interesting. I have an NAD player here that has it, but is infected with
opamps and needs to be cured from this horrible disease.
> I have already figured out the topology and pinout but would like to know
something more about the internal setup and just have the d**ned sheet...
>
Hi,
Sice I know you're very good with languages:
Here you can find some genral info
http://www.56789.com/data/253.htm
This one probably links to the datasheet:
http://www.cgc.co.jp/bbj/products/PCM.html
Here's a link to a joelist digest, with the pressrelease:
http://www.sw.com.sg/~oleg/sound-digest/v01.n430
And by now you will get tired of this, so here's the file itself:
http://www.audiocom-uk.com/Data_Sheets/PCM1732.pdf
(if downloading doesn't work, I saved the file, so I can send it by email)
Have fun!
Greetz,
Raymond
=========================================================================
From: Remco Stoutjesdijk <remco@ultranalog.com>
Subject: Re: [JN] Wanted dead or alive: BB PCM1732 datasheet
Date: Sat, 18 Aug 2001 21:19:02 +0200
Source: Sound Digest Archive v02.n949
Ah! Even a longshot works around here.
>And by now you will get tired of this, so here's the file itself:
>http://www.audiocom-uk.com/Data_Sheets/PCM1732.pdf
Yes! audiocom didn't have it yesterday (broken link). Great. Thanx Raymond, and all others who offer
ed help!
I now see I can tap audio out even before the lowpass filter. Kewl. Too bad this baby's single ended
, but maybe the HDCD makes up for that.
Well, let's get to work!
Thanks again,
Remco
- --
http://www.ultranalog.com
=========================================================================
From: David Home <David_Home@creoscitex.com>
Subject: RE: [JN] Wanted dead or alive: BB PCM1732 datasheet
Date: Tue, 21 Aug 2001 10:11:53 +0200
Source: Sound Digest Archive v02.n951
Can't find the datasheet for the PCM 1702 either.
Anyone got it or point me to it?
Regards, David
- -----Original Message-----
From: Remco Stoutjesdijk [mailto:remco@ultranalog.com]
Sent: Friday, August 17, 2001 9:59 PM
To: sound@lists.io.com
Subject: [JN] Wanted dead or alive: BB PCM1732 datasheet
Gang,
Longshot:
Is there anybody out there who has this datasheet somewhere? It has been
available for a while, but now Burr-Brown doesn't have it online anymore,
probably since it's the world's first HDCD + DAC integrated chip. Looks
interesting. I have an NAD player here that has it, but is infected with
opamps and needs to be cured from this horrible disease.
I have already figured out the topology and pinout but would like to know
something more about the internal setup and just have the d**ned sheet...
TIA,
Remco
- --
http://www.ultranalog.com
=========================================================================
From: "Mai, Jeff" <Jeff.Mai@sunmed.com>
Subject: [JN] Wanted: dead preamp
Date: Wed, 10 Jan 2001 12:42:10 -0700
Source: Sound Digest Archive v02.n780
I'm looking for a dead SS preamp for a project. It needs to be a minimum of
3 inches tall, otherwise I prefer a smaller chassis. I'll be using the
knobs, switching controls and RCA jacks. Nothing else needs to work.
Email me off list if you've got something like this. I've got a few cool
things to trade or I'll pay green money.
Jeff
=========================================================================
From: "Eric Weitzman" <eweitzman@acm.org>
Subject: [JN] wanted: DQ10 crossover schematic
Date: Wed, 13 Dec 2000 08:24:20 -0800
Source: Sound Digest Archive v02.n758
Does anyone have a schematic for the crossover in the Dahlquist DQ10 loudspeaker?
Thanks,
- - Eric
=========================================================================
From: Paul Butterfield <paulbutterfield@mindspring.com>
Subject: Re: [JN] wanted: DQ10 crossover schematic
Date: Thu, 14 Dec 2000 09:14:22 -0500
Source: Sound Digest Archive v02.n758
Hi Eric,
One of our local CFAS members has rebuilt and modified three pairs of
DQ10s. I'll forward your request over to him.
Best, Paul B
Eric Weitzman wrote:
>
> Does anyone have a schematic for the crossover in the Dahlquist DQ10 loudspeaker?
>
> Thanks,
> - Eric
- --
Paul Butterfield
Central Florida Audio Society
TAD 2001 Recovery Project
paulbutterfield@usa.net
paulbutterfield@mindspring.com
407/645-1111 Voice number
407/647-1177 Voice/Data
"Those who hear not the music think the dancers mad."
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
=========================================================================
From: David Barnett <d_n_b@swbell.net>
Subject: Re: [JN] wanted: DQ10 crossover schematic
Date: Thu, 14 Dec 2000 11:31:31 -0600
Source: Sound Digest Archive v02.n759
On Wed, 13 Dec 2000 08:24:20 -0800, Eric Weitzman <eweitzman@acm.org>
wrote:
>Does anyone have a schematic for the crossover in the Dahlquist DQ10 loudspeaker?
I think I can draw it from memory. It's a nightmare of series and
parallel sections -- the woofer and mid are in series, which is in
parallell with the series-connected pair of domes, then the piezo is
fed off the dome tweeter with some additional filtering. Send me your
snail-mail address and I'll shoot you a quick drawing.
- --dnb
=========================================================================
From: "Ron & Tamara" <ron.steinberg@sympatico.ca>
Subject: Re: [JN] wanted: DQ10 crossover schematic
Date: Thu, 14 Dec 2000 12:18:32 -0400
Source: Sound Digest Archive v02.n759
Eric, you're the second person in 4 days that I know that has requested
this! Well you're in luck 'cause I have it on my web site. Check out:
http://www3.sympatico.ca/ron.steinberg/DQ10crossover.gif
Cheers,
Ron
- ----------
>From: "Eric Weitzman" <eweitzman@acm.org>
>To: <sound@lists.io.com>
>Subject: [JN] wanted: DQ10 crossover schematic
>Date: Wed, Dec 13, 2000, 12:24 PM
>
> Does anyone have a schematic for the crossover in the Dahlquist DQ10
loudspeaker?
>
> Thanks,
> - Eric
=========================================================================
From: rcjones1@mmm.com
Subject: [JN] Wanted: EL509's and adapter sockets.
Date: Tue, 23 Oct 2001 08:53:25 -0500
Source: Sound Digest Archive v02.n994
Hi there,
wow this list is quiet.
Anyhow, I decided on EL509's for my CF. A lot more rugged. Anyone have
any CHEAP ones? I need 8 total. Also is there any sockets for these that
have the screw terminals like the octal relay sockets?
Anyhow I am thinking of 70-80v anode, 150v g3.
any thoughts?
Richard
=========================================================================
From: rcjones1@mmm.com
Subject: [JN] wanted : GZ37 pair
Date: Tue, 22 May 2001 11:11:03 -0500
Source: Sound Digest Archive v02.n890
Hi joenetters,
I know this is a wanted ad, but I am looking for a pair of GZ37 rectifiers.
Preferably in the US.
Thanks
RIchard
=========================================================================
From: "Multi-Volti Devices" <multi-volti@softhouse.com>
Subject: [JN] wanted Hickok TV-3B/U NAVSHIPS 91747 manual
Date: Thu, 15 Jul 1999 00:49:28 -0400
Source: Sound Digest Archive v02.n205
wanted Hickok TV-3B/U NAVSHIPS 91747 manual
Thanks
Murray
Multi-Volti@softhouse.com
=========================================================================
From: Ed Billeci <tube@teleport.com>
Subject: [JN] Wanted: JBL H-92 / 2312 horn (x1) / Subs for sale
Date: Fri, 23 Feb 2001 08:48:58 -0800
Source: Sound Digest Archive v02.n816
If you have one of these horns for sale, please let me know.
BTW, I have some of the Linkwitz style open baffle subs for sale, with the
X6100 drivers. Built according to plans @ http://www.linkwitzlab/woofer.htm
includes (4) subs total, total of (x8) drivers, barely used. (still not
broken in) $300 all if you pick them up in Portland. If you want these
shipped, it is $350 / all, and I will deliver them to a shipper/packaging
Co. (you would have to arrange transport and packing from there.)
This is obviously much less than they cost to build. Why am I selling?
The subs are not able to be crossed over to my Chapman horn/TAD midrange.
The crossover point is too high for the Linkwitz subs and this creates a
"gap" between 125hz to 250 hz. I am currently building subs that will
crossover at the required 250 hz. If you know of anyone who needs good
subs, please let them know, as I hate to see these sitting around un-used.
Ed B.
Portland, OR
http://www.teleport.com/~tube
=========================================================================
From: "Epstein, Jeremy" <JEpstein@ndbcap.com>
Subject: [JN] Wanted : Large Advent Tweeters
Date: Fri, 2 Jun 2000 15:18:46 -0400
Source: Sound Digest Archive v02.n562
I am using the tweeters from a junked pair of Large Advents with my TQWP
experimental speaker testbeds and they sound pretty good. The ones I'm using
came out of the trash, and, well, let's just say my attempts to pull a dent
out of one tweeter dome weren't fully successful. Anybody have any of these
lying around?
The tweeter is an amber paper cone in the shape of a convex dome with a
convex half-roll around it. (Cross section : nnn ) The surround attaches to
a thin masonite (or impregnated cardboard?) square board oriented as a
diamond, about 3/8" behind this is a square steel plate which holds the
square magnet assembly and the terminals. You'd know it if you saw it.
Anyway what with the big dent in the one dome and the fact that I want to
build another pair of these for my brother, I got to thinking I should cast
about for some more of these. I guess I could always BUY something but I
thought I'd rattle the collective junk-box first.
Rattling!
- -j
=========================================
Jeremy Epstein........jepstein@ndbcap.com
=========================================
=========================================================================
From: David Dlugos <planet10@pinc.com>
Subject: Re: [JN] Wanted : Large Advent Tweeters
Date: Fri, 2 Jun 2000 18:52:27 -0700
Source: Sound Digest Archive v02.n562
>>The ones I'm using
>>came out of the trash, and, well, let's just say my attempts to pull a dent
>>out of one tweeter dome weren't fully successful.
>
>Have you tried kissing out the dent with your mouth? I'm serious.
On the BASSList this is known as the Monica Lewinsky method. And it often
does work.
dave
______________________
Trust your ears, listen, practice hard
=========================================================================
From: "PEARL Cust Serv" <custserv@pearl-hifi.com>
Subject: Re: [JN] Wanted : Large Advent Tweeters
Date: Fri, 02 Jun 2000 20:12:08 -0600
Source: Sound Digest Archive v02.n562
>>>The ones I'm using
>>>came out of the trash, and, well, let's just say my attempts to pull a dent
>>>out of one tweeter dome weren't fully successful.
>>
>>Have you tried kissing out the dent with your mouth? I'm serious.
>
> On the BASSList this is known as the Monica Lewinsky method. And it often
> does work.
>
> dave
>
. . . . just don't swallow . . . . the Ferrofluid . . . .
Anonymous Contribution :>)
=========================================================================
From: David Barnett <d_n_b@swbell.net>
Subject: Re: [JN] Wanted : Large Advent Tweeters
Date: Fri, 02 Jun 2000 20:25:41 -0500
Source: Sound Digest Archive v02.n562
On Fri, 02 Jun 2000 15:18:46 -0400, "Epstein, Jeremy"
<JEpstein@ndbcap.com> wrote:
>The ones I'm using
>came out of the trash, and, well, let's just say my attempts to pull a dent
>out of one tweeter dome weren't fully successful.
Have you tried kissing out the dent with your mouth? I'm serious.
- --dnb
=========================================================================
From: Richard C Nevill <rnevill@is.dal.ca>
Subject: Re: [JN] Wanted : Large Advent Tweeters
Date: Fri, 2 Jun 2000 22:42:35 -0300 (ADT)
Source: Sound Digest Archive v02.n562
On Fri, 2 Jun 2000, David Barnett wrote:
> On Fri, 02 Jun 2000 15:18:46 -0400, "Epstein, Jeremy"
> <JEpstein@ndbcap.com> wrote:
>
> >The ones I'm using
> >came out of the trash, and, well, let's just say my attempts to pull a dent
> >out of one tweeter dome weren't fully successful.
>
> Have you tried kissing out the dent with your mouth? I'm serious.
>
> --dnb
I had some luck using a really old vaccumm cleaner with all its vents
open, even the top open. Left some very minor creases in the paper but
seemed to work.
Cheers
Richard Nevill
>
>
=========================================================================
From: David Barnett <d_n_b@swbell.net>
Subject: Re: [JN] Wanted : Large Advent Tweeters
Date: Sat, 03 Jun 2000 03:39:15 -0500
Source: Sound Digest Archive v02.n562
On Fri, 02 Jun 2000 18:52:27 -0700, David Dlugos <planet10@pinc.com>
wrote:
>>Have you tried kissing out the dent with your mouth? I'm serious.
>
>On the BASSList this is known as the Monica Lewinsky method. And it often
>does work.
Where does the cigar fit in?
- --dnb
=========================================================================
From: "Ellen Oler" <ellenoler@earthlink.net>
Subject: Re : [JN] Wanted : Large Advent Tweeters
Date: Sat, 03 Jun 2000 08:59:36 -0400
Source: Sound Digest Archive v02.n563
>From: David Barnett <d_n_b@swbell.net>
><JEpstein@ndbcap.com> wrote:
>>The ones I'm using
>>came out of the trash, and, well, let's just say my attempts to pull a dent
>>out of one tweeter dome weren't fully successful.
>Have you tried kissing out the dent with your mouth? I'm serious.
Tried that.
>From: Richard C Nevill <rnevill@is.dal.ca>
>I had some luck using a really old vaccumm cleaner with all its vents
>open, even the top open. Left some very minor creases in the paper but
>seemed to work.
Tried that. Tried sticky tape too.
>From: David Dlugos <planet10@pinc.com>
>On the BASSList this is known as the Monica Lewinsky method. And it often
>does work.
Sorry, I don't smoke cigars.
;-)
Thanks, everybody!
PS : one Joe was kind enough to tell me where I could buy these. However,
I'm looking for a somewhat lower cost basis than new retail - what I told
him was, if the average Joe is anything like me, he drags these into his
garage after seeing them on the curb, and then 2 years later is saying "What
the hell am I going to do with these things?"
Me, I'm just trying to help clean out YOUR garage, Mr. Average Joe! And if I
have to pop full retail I'll probably buy something a little nicer.
- -j (Jeremy Epstein again, this time from home)
=========================================================================
From: "=?ISO-8859-1?Q?Torbj=F8rn_Lien?=" <mdrivekl@online.no>
Subject: Re: [JN] Wanted: Large Current Power transformer
Date: Wed, 3 Feb 1999 00:05:08 +0100
Source: Sound Digest Archive v02.n024
> Hmmmm...can't resist this one
>
> This is an interesting comparison...basically the old accuracy
> vs. pleasing sound schism
>
> the most popular guitar amp circuits are the old school stuff w/
> small caps, small or no chokes, cathode bias, tube ectification.
> Pleasing distortion and warm clean sound are the benchmarks,
> strictly ear and taste driven...BTW all guitar amp speakers
> start to roll off around 5-6k...this is the classic sound.
>
Yepp, I fully agree,-this is *the* classic sound,-but also the
coloured, compressed, noisy, distorted, warm, etc. sound that defined
the sound of the electric guitar *right* from the start,- The sound of
electric blues and rocn'roll,-of course this can't
be "improved" upon,-It would be a tech. dumb try to change the
instruments and music itselves....
> Most guitar players HATE fast, accurate sounding solid state
> amps...too unforgiving, powerful and annoying sounding.
Solid state amps yes...And in general you are right. But there
are guitar players that love "accurate" or modern, or whatever
you call this setup aswell,-The challenge of mastering this "magnifying
glass" approach.. Especially skilled musicians that
do tapping and other kinds of modern techniques,-
> Bass players tend to like more powerful, accurate sounding tube >amps
like SVT, but who wants to carry 100 lbs to every gig?
I do,-I have a car though..One guitarist I play with find my rig to be
useless,-for guitar...But he keeps asking me of building
him a small scale version,-for home practise.Cause whenever he plugs
on, he faces his own "limitations",-or inaccuracies of fingering
technique. I do aswell,-but I can't give up this access to a real
dynamic, or responsive sound. I guess compressors are not for me....
[snip]
> I sat down w/ jc and we designed and built an amp that had
> excellent numbers using 6550's, hexfreds, ultralinear,
> big caps, etc. Guess what? It was no FUN to listen to!!!
> Pointless, sonically.
Yes, I *do* believe this aswell,-ofcourse there's more to it
than big caps,-there is just so many factors that comes to play
here,-My initial remarks about PSU's was more to be read like
this: Make an unmoveable stiff PSU with low common mode noise,-
Then you can just forget it and move on to the circuit itselves..
IMHO a good supply might reveal the uselessness of the
ultralinear circuit pretty fast.....
Regards,
Torbjoern Lien
>
>
>
>
=========================================================================
From: "G. Johnston" <garywj@home.com>
Subject: [JN] Wanted: Large Current Power transformers
Date: Sat, 30 Jan 1999 11:50:50 +0900
Source: Sound Digest Archive v02.n017
Hey Gang,
I am looking for a nice set of used, or new(nos), power transformers to
fuel my "Flesh and Bloods".
I believe that Herb himself is using toroids, but I would like to locate
something which is comparable in a standard bell type-if I am not
mistaken, he is recommending 400-0-400 at 500Ma. I tried to get a quote
on some made here in the states and the cost would be around $300 min.
Ouch!
Just asking if anybody had some serious chunks of iron around that they
might be willing to part with.
Gary
=========================================================================
From: Chris Beck <n9zes@execpc.com>
Subject: Re: [JN] Wanted: Large Current Power transformers
Date: Sun, 31 Jan 1999 07:11:26 -0600
Source: Sound Digest Archive v02.n017
If you want my 2 cents worth, try the Hammond transformers. I don't think
they have anything THAT big, but sheesh, 500mA is overkill, in my opinion.
What's a 300B gonna use? 60mA, 80mA? A 200 mA tranny should me more than
enough. I know what Herb is saying, I've read his article. It makes
sense. But, it all depends on how much you want to spend.
But, I have not heard his amp with ANY power supply, so this is all totally
my opinion. Proceed at your own risk! :-)
Chris Beck
see my webpage at: http://www.execpc.com/~n9zes
"G. Johnston" wrote:
> Hey Gang,
>
> I am looking for a nice set of used, or new(nos), power transformers to
> fuel my "Flesh and Bloods".
>
> I believe that Herb himself is using toroids, but I would like to locate
> something which is comparable in a standard bell type-if I am not
> mistaken, he is recommending 400-0-400 at 500Ma. I tried to get a quote
> on some made here in the states and the cost would be around $300 min.
> Ouch!
>
> Just asking if anybody had some serious chunks of iron around that they
> might be willing to part with.
>
> Gary
=========================================================================
From: spence barton <ence-ack@rio.com>
Subject: Re: [JN] Wanted: Large Current Power transformers
Date: Sun, 31 Jan 1999 10:48:10 -0800
Source: Sound Digest Archive v02.n018
> If you want my 2 cents worth, try the Hammond transformers. I don't think
> they have anything THAT big, but sheesh, 500mA is overkill, in my opinion.
> What's a 300B gonna use? 60mA, 80mA? A 200 mA tranny should me more than
> enough. I know what Herb is saying, I've read his article. It makes
> sense. But, it all depends on how much you want to spend.
>
> But, I have not heard his amp with ANY power supply, so this is all totally
> my opinion. Proceed at your own risk! :-)
It's always wonderful to have an idea shot down by someone who's NEVER
TRIED IT. That's what I really like about this list and I why I ALMOST
NEVER post anymore. Here a guy asks for help finding a transformer and
shares the information that high current transformers can make a
difference and someone who's never tried it tells him not to bother. For
heavens sake.
I use power supply transformers which are rated at 750 mA. I noticed
some substantial, across-the-board improvements and posted about them to
the list. If most of the other ducks are in a row in an amp, this can be
a really good thing to do. Getting an amp to sound good takes a whole
lot more than adding up the current draws and supply that current.
Saying a power transformer can supply a lot of current is just another
way of say that it is very low impedance. Ignore voltage it's only the
shadow of current which is what's really important. Big iron, small (no)
caps. Yesirree.
An amp built with a great power supply and a cheap chinese 2A3 will
smoke an amp with a crummy supply and the most expensive output tube
made. Power amps are a lot more current amplifiers than they are voltage
amplifiers. Speakers are current operated devices.
spence
=========================================================================
From: Ken Gilbert <ride5000@ride.ri.net>
Subject: Re: [JN] Wanted: Large Current Power transformers
Date: Sun, 31 Jan 1999 13:25:30 -0500
Source: Sound Digest Archive v02.n018
At 11:50 AM 1/30/99 +0900, you wrote:
>Hey Gang,
>I believe that Herb himself is using toroids, but I would like to locate
>something which is comparable in a standard bell type-if I am not
>mistaken, he is recommending 400-0-400 at 500Ma. I tried to get a quote
>on some made here in the states and the cost would be around $300 min.
>Ouch!
Hammond makes a dedicated plate tranny (one of the 7xx series) that's
425-0-425 and good for 450 mADC ICAS. It's 8.8 pounds.
You could also go choke input and get better current specs out of a tranny.
Real estate, cost, and weight come into play of course. I am not familiar
with the design of the PS you have in mind, so I can't really comment on that.
Myself, I am using a DIY toroid. Still winding it though...
kg
Ken Gilbert
http://www.geocities.com/SunsetStrip/Garage/5701
- ------------------------------------------------
Tube Guitar Amplifier Repair/Design Technician
The Guitarist's Choice Inc. http://www.tgcguitar.com
=========================================================================
From: "E. Billeci" <tube@teleport.com>
Subject: Re: [JN] Wanted: Large Current Power transformers
Date: Sun, 31 Jan 1999 14:35:59 -0600
Source: Sound Digest Archive v02.n018
At 10:48 AM 1/31/99 -0800, you wrote:
[great stuff snipped]
>I use power supply transformers which are rated at 750 mA. I noticed
>some substantial, across-the-board improvements and posted about them to
>the list. If most of the other ducks are in a row in an amp, this can be
>a really good thing to do. Getting an amp to sound good takes a whole
>lot more than adding up the current draws and supply that current.
>Saying a power transformer can supply a lot of current is just another
>way of say that it is very low impedance. Ignore voltage it's only the
>shadow of current which is what's really important. Big iron, small (no)
>caps. Yesirree.
Agreed. Another thing some people (cough) forget, is that you gotta draw
the line somewhere. There is a fine
balance between maximizing sound quality, and still being able to move the
thing when it is done. I have been in the process of reducing the size and
weight of a largish 212 S.E. amp I built a couple of years ago. I found
that the two main culprits are big iron, and big oil
caps.(www.teleport.com/~tube)
I suggest using toroids as Spence does, and also suggest using toroidal
common-mode chokes in the power supply. As far as the caps go, the newer
oil/poly caps are low ESR, and smaller than the older, larger square can
types. They are also round, so it makes for many interesting options as far
as chassis design goes. As you know, those toroids are hard to beat for
space considerations. How else can you tuck a 12amp fil trans under your
chassis? ( most people are smart enough to stay away from tubes with 100
watt fils )
It would be possible to use toroids for all your iron (parafeed opt) if
you so desired, but would probably require the builder to pay alot more
attention to balancing his house A-C power feed- a great idea in any case.
Ed Billeci
www.teleport.com/~tube
=========================================================================
From: "PEARL Cust Serv" <custserv@pearl-hifi.com>
Subject: Re: [JN] Wanted: Large Current Power transformers
Date: Sun, 31 Jan 1999 16:11:02 -0700
Source: Sound Digest Archive v02.n018
>From: "E. Billeci" <tube@teleport.com>
> At 10:48 AM 1/31/99 -0800, you wrote:
>
> [great stuff snipped]
>>I use power supply transformers which are rated at 750 mA. I noticed
>>some substantial, across-the-board improvements and posted about them to
>>the list. If most of the other ducks are in a row in an amp, this can be
>>a really good thing to do. Getting an amp to sound good takes a whole
>>lot more than adding up the current draws and supply that current.
>>Saying a power transformer can supply a lot of current is just another
>>way of say that it is very low impedance. Ignore voltage it's only the
>>shadow of current which is what's really important. Big iron, small (no)
>>caps. Yesirree.
>
> Agreed. Another thing some people (cough) forget, is that you gotta draw
> the line somewhere. There is a fine
> balance between maximizing sound quality, and still being able to move the
> thing when it is done. I have been in the process of reducing the size and
> weight of a largish 212 S.E. amp I built a couple of years ago. I found
> that the two main culprits are big iron, and big oil
> caps.(www.teleport.com/~tube)
>
> I suggest using toroids as Spence does, and also suggest using toroidal
> common-mode chokes in the power supply. As far as the caps go, the newer
> oil/poly caps are low ESR, and smaller than the older, larger square can
> types. They are also round, so it makes for many interesting options as far
> as chassis design goes. As you know, those toroids are hard to beat for
> space considerations. How else can you tuck a 12amp fil trans under your
> chassis? ( most people are smart enough to stay away from tubes with 100
> watt fils )
> It would be possible to use toroids for all your iron (parafeed opt) if
> you so desired, but would probably require the builder to pay alot more
> attention to balancing his house A-C power feed- a great idea in any case.
>
>
> Ed Billeci
> www.teleport.com/~tube
>
===============================
Hi All:
You know, it's really too bad that PTs built on c-cores aren't more
commonly available. As I've said before, toroids exhibt very extended
frequency response and this is that last thing wanted in a PT.
While it's true that the excitation current in a toroid is much lower
(essentially the current drawn by the transformer when running with no load
on the secondary), the trade-off is a greatly increased susceptibility to
saturation by assymmetical input waveforms... and these occur all the time
on the AC line.
E-I stacks are at the bottom of the barrel in almost every parameter,
ungapped toriods excel in a few ways, but are, in many ways, an unbalaced
approach to the problem. Gapped c-core devices are the best balance for most
audio work.
Bill - PEARL.
=========================================================================
From: "PEARL Cust Serv" <custserv@pearl-hifi.com>
Subject: Re: [JN] Wanted: Large Current Power transformers
Date: Sun, 31 Jan 1999 16:18:05 -0700
Source: Sound Digest Archive v02.n018
>From: spence barton <ence-ack@rio.com>
€ Snip €
>
> I use power supply transformers which are rated at 750 mA. I noticed
> some substantial, across-the-board improvements and posted about them to
> the list. If most of the other ducks are in a row in an amp, this can be
> a really good thing to do. Getting an amp to sound good takes a whole
> lot more than adding up the current draws and supply that current.
> Saying a power transformer can supply a lot of current is just another
> way of say that it is very low impedance. Ignore voltage it's only the
> shadow of current which is what's really important. Big iron, small (no)
> caps. Yesirree.
>
> An amp built with a great power supply and a cheap chinese 2A3 will
> smoke an amp with a crummy supply and the most expensive output tube
> made. Power amps are a lot more current amplifiers than they are voltage
> amplifiers. Speakers are current operated devices.
€ Dynamic speakers anyway, ESLs are, in large measure,
voltage operated; a point commonly overlooked. €
>
>
> spence
================================
Hi All:
Over the years, I've given this particular observation a lot of thought
and while I have a few nascent ideas about why this might be so, I've failed
to arrived at any satisfying notions.... any ideas that might allow me to
come up with a more elegant alternative to this seemingly "brute force"
approach.
My experience is that while brute force will get you to a workable
result, something interesting always happens when understanding dawns and
something more sophisticated can be developed..
Bill - PEARL
=========================================================================
From: "Larry D. Moore" <l-moore@onu.edu>
Subject: Re: [JN] Wanted: Large Current Power transformers
Date: Sun, 31 Jan 1999 17:01:59 -0500
Source: Sound Digest Archive v02.n018
Spence:
I'm locked and loaded! I got your backside covered! I'm for the power tx
higher current capability too.
L.D. Moore
<BIG SNIP>
=========================================================================
From: Chris Beck <n9zes@execpc.com>
Subject: Re: [JN] Wanted: Large Current Power transformers
Date: Sun, 31 Jan 1999 18:00:13 -0600
Source: Sound Digest Archive v02.n018
Does anyone have mathematical proof or even theory why such large, low impedance
supplies make such a difference to our amps? I can understand this line of
pursuit when trying to run a big PP class AB amp, with the large current swings
necessary. But, for class A amps, the only current variation is the
instantaneous change with signal in the output tranny. Am I correct?? This is
handled by the last capacitor in the supply, from what I've gathered.
I'm really trying to understand this all, as I too have read the posts here
about big, low DCR chokes, thyratron rectifiers, etc, and have tried to
understand how this affects the amp. I find it all quite interesting.
Thanks for any insight!
Chris
PEARL Cust Serv wrote:
> >From: spence barton <ence-ack@rio.com>
>
> € Snip €
> >
> > I use power supply transformers which are rated at 750 mA. I noticed
> > some substantial, across-the-board improvements and posted about them to
> > the list. If most of the other ducks are in a row in an amp, this can be
> > a really good thing to do. Getting an amp to sound good takes a whole
> > lot more than adding up the current draws and supply that current.
> > Saying a power transformer can supply a lot of current is just another
> > way of say that it is very low impedance. Ignore voltage it's only the
> > shadow of current which is what's really important. Big iron, small (no)
> > caps. Yesirree.
> >
> > An amp built with a great power supply and a cheap chinese 2A3 will
> > smoke an amp with a crummy supply and the most expensive output tube
> > made. Power amps are a lot more current amplifiers than they are voltage
> > amplifiers. Speakers are current operated devices.
> € Dynamic speakers anyway, ESLs are, in large measure,
> voltage operated; a point commonly overlooked. €
> >
> >
> > spence
>
> ================================
>
> Hi All:
> Over the years, I've given this particular observation a lot of thought
> and while I have a few nascent ideas about why this might be so, I've failed
> to arrived at any satisfying notions.... any ideas that might allow me to
> come up with a more elegant alternative to this seemingly "brute force"
> approach.
> My experience is that while brute force will get you to a workable
> result, something interesting always happens when understanding dawns and
> something more sophisticated can be developed..
>
> Bill - PEARL
=========================================================================
From: "Ferenc Koscso" <vektorbp@mail.datanet.hu>
Subject: Re: [JN] Wanted: Large Current Power transformers
Date: Sun, 31 Jan 1999 18:46:16 +0100
Source: Sound Digest Archive v02.n018
I am using toroid power tranny for my DC coupled 45 triode monoblock amp.
One is 200VA toroid for the 6SL7 input and another 300VA for the output
stage. I paid about $55 for the smaller and about $65 for the bigger one,
they are made by a Hungarian tranny maker, it was the smallest power they
make, this is the reason why I bought so big. They are very quiet, no
buzzing. I know it is overkill, size is really big (OD 120 and 130 mm,
height is 55 and 68 mm) but their dynamics, body and smoothness is really
nice, better than my former Audio Note was.
Ferenc
- ----------
>From: "G. Johnston" <garywj@home.com>
>To: "'Sound Practices'" <sound@lists.io.com>
>Subject: [JN] Wanted: Large Current Power transformers
>Date: Sat, Jan 30, 1999, 3:50 AM
>
> Hey Gang,
>
> I am looking for a nice set of used, or new(nos), power transformers to
> fuel my "Flesh and Bloods".
>
> I believe that Herb himself is using toroids, but I would like to locate
> something which is comparable in a standard bell type-if I am not
> mistaken, he is recommending 400-0-400 at 500Ma. I tried to get a quote
> on some made here in the states and the cost would be around $300 min.
> Ouch!
>
> Just asking if anybody had some serious chunks of iron around that they
> might be willing to part with.
>
> Gary
=========================================================================
From: Allen Wright <AllenVSE@compuserve.com>
Subject: Re: [JN] Wanted: Large Current Power transformers
Date: Mon, 1 Feb 1999 03:36:15 -0500
Source: Sound Digest Archive v02.n018
Spence wrote:
>>>It's always wonderful to have an idea shot down by someone who's NEVER
TRIED IT. That's what I really like about this list and I why I ALMOST
NEVER post anymore. Here a guy asks for help finding a transformer and
shares the information that high current transformers can make a
difference and someone who's never tried it tells him not to bother. For
heavens sake<<<
Right On! There are facts and experience, and then there are opinions...
Allen (VSE)
=========================================================================
From: pitaro@ozemail.com.au
Subject: Re: [JN] Wanted: Large Current Power transformers
Date: Mon, 1 Feb 1999 17:19:37 EST
Source: Sound Digest Archive v02.n018
Hi all,
Does the large current capabilities in a power tranny improve the
regulation of the power transformer? Maybe that's the advantage that
people are hearing.
I've been told by my power tranny winder that most power trannies have
about 7% regulation. I've ordered some with 1% regulation trannies and the
size of the iron is about 3 times bigger. I don't know what the regulation
is for an average toroid.
Just a thought.
Regards,
Harry Pitaro
+-----------------------+---------------------------------------------+
| Melbourne, Australia | A good discussion is like a miniskirt; |
| | Short enough to retain interest |
| pitaro@ozemail.com.au | and long enough to cover the subject. |
+-----------------------+---------------------------------------------+
=========================================================================
From: Steve Berger <aprilsound@earthlink.net>
Subject: Re: [JN] Wanted: Large Current Power transformers
Date: Mon, 01 Feb 1999 10:33:20 -0500
Source: Sound Digest Archive v02.n019
spence barton wrote:
>
> > If you want my 2 cents worth, try the Hammond transformers. I don't think
> > they have anything THAT big, but sheesh, 500mA is overkill, in my opinion.
> > What's a 300B gonna use? 60mA, 80mA? A 200 mA tranny should me more than
> > enough. I know what Herb is saying, I've read his article. It makes
> > sense. But, it all depends on how much you want to spend.
> >
> > But, I have not heard his amp with ANY power supply, so this is all totally
> > my opinion. Proceed at your own risk! :-)
>
> It's always wonderful to have an idea shot down by someone who's NEVER
> TRIED IT. That's what I really like about this list and I why I ALMOST
> NEVER post anymore. Here a guy asks for help finding a transformer and
> shares the information that high current transformers can make a
> difference and someone who's never tried it tells him not to bother. For
> heavens sake.
>
> I use power supply transformers which are rated at 750 mA. I noticed
> some substantial, across-the-board improvements and posted about them to
> the list. If most of the other ducks are in a row in an amp, this can be
> a really good thing to do. Getting an amp to sound good takes a whole
> lot more than adding up the current draws and supply that current.
> Saying a power transformer can supply a lot of current is just another
> way of say that it is very low impedance. Ignore voltage it's only the
> shadow of current which is what's really important. Big iron, small (no)
> caps. Yesirree.
>
> An amp built with a great power supply and a cheap chinese 2A3 will
> smoke an amp with a crummy supply and the most expensive output tube
> made. Power amps are a lot more current amplifiers than they are voltage
> amplifiers. Speakers are current operated devices.
>
> spence
Hear Hear Spence!!:
Folks, There is NO free sonic lunch!{J.C.Morisson,circa 1994}.
If you want to just have fun, use your dumpster junk. This is fine, it
just wont get you to where I want to be.
Untill you've been there, its absurd to make coments like "current
reserve doesnt matter" or "large, Low DCR chokes Cant make a diference"
Give me a F#%#ing break. I got a call from a guy who told me that he got
the GREATEST sound from a pair of PP trannys out of an old reciever.
I said to him"with all due respect sir, what you've got is the taste of
what SE can do".I think that this is more whats going on here than
anything. Its so exiteing to put something together and see it work that
it HAS to be the best thing youve ever heard. The truth is,it probably
IS a damn sight better than most of the crap that you can buy at the
Wiz.
Guys like Spence, Dave "clippy" Slagle are guys you should really
listen to. They have both spent the time and the bucks to find out whats
what.
Large Low DCR chokes small caps high current power trannys, OH BABY!
Steve
PS: OH!, did I forget to mention sound design and TASTE?
- --
Steve Berger <http://home.earthlink.net/~aprilsound/>
=========================================================================
From: "Chris Beck" <cbeck@brewercompany.com>
Subject: Re: [JN] Wanted: Large Current Power transformers
Date: Mon, 1 Feb 1999 13:49:14 -0600
Source: Sound Digest Archive v02.n019
Okay, I'm starting to see the light here. One question I have is how does
the relationship of power supply capacity (that is: big mondo trannies)
have with the capacitance of the supply? It seems that the preference is
for big iron/small caps. There must be a limit how small you can go with
caps before hum gets too bad? On the other hand, why can't we use a
transformer that handles just what we need and just throw tons of uF at it
as a reservoir to handle the current variation?
The supply I use in my amps is 200mA tranny,Rectifier is 5R4, then 10uF,
10H choke with 92 ohms DCR, and 50uF of polyprop/oil caps to the output
tranny. . Then another 40uF to the driver after a dropper resistor. I
draw around 120-140mA from this supply. A rather "textbook" supply.
I really find this very interesting, as this is the sort of thing that has
to be heard to be understood, no? Equations help, math helps, but the
proof is in the pudding, and this is where I don't have much experience,
I'm afraid. I've always understood that if you have enough capacitance at
the final end of the filter, you are in good shape. However, as you draw
currrent from this cap on an instantaneous basis, the voltage drops, no
matter how big the cap (within reason). Having a low Z supply feeding it
allows the output stage to draw directly from the AC supply so to speak,
which is relatively limitless. This keeps the operating point of the tube
constant which lowers the dynamic distortion, as Kurt mentioned.
Now, a cap input filter charges in a series of pulses from the AC, right?
What happens to the low impedance supply when a big transient comes along
between charging pulses from the rectifier?
Thanks for the bandwidth. I really want to understand the WHY of how this
works. I certainly don't say that monster supplies are ridiculous, etc.
Like Spence said, he's been there, done that, along with Mr. Slagle. I
just want to know what makes them tick.
Chris Beck
See my web page at: http://www.execpc.com/~n9zes/index.htm
- ----------
> From: Kurt Steffensen <solvin-aurum@get2net.dk>
> To: Chris Beck <n9zes@execpc.com>
> Cc: PEARL Cust Serv <custserv@pearl-hifi.com>; sound@lists.io.com
> Subject: Re: [JN] Wanted: Large Current Power transformers
> Date: Monday, February 01, 1999 11:31 AM
>
> Dear Chris , and all other interested.
>
> Chris Beck skrev:
>
> > Does anyone have mathematical proof or even theory why such large, low
impedance
> > supplies make such a difference to our amps?
>
> Yes, I do, to the degree that mathematics proofs anything in this
matter.
>
> The delta current that is drawn from the amplifier , changes the voltage
to be
> supplied to the same , with the value of the Z-out in the PSU. (dI x Z )
> If the delta current is 100mA , and the Z of the transformer is say 300
Ohm ,
> then the voltage change is at least 60 Volts.(The small iron mass ads to
this)
>
> As all these happens very fast , but fully within the audio range , these
changes ,
> appears as "ringning" or fast unpredictable oscillations.(Not visuable
with sines)
> Further is influence the dynamics , and power output of the system.
> The ringning is mainly due to the reaction between the Z of the
transformer ,
> and the capacity of the capacitors.
>
> Low-Z , transformers and low DC-Ohm chokes, and LOTS of uF´s , makes
> the amplifier more , dynamic ,steady and lowers the DYNAMIC distortion.
>
> It simply sounds a lot better , the lower the impedance , the PSU can do.
>
> The regulated ones surely are the best , but one can do good , with big
> transformers,
> chokes and capacitors.
>
> You really do not need the mathematical proof , Chris, you can hear it
instantly ,
> if you try to compare.
>
> Like our good Bill (Perkins) , I do preferes the EI or C-cores.
> But the difference is not big.... It is just audiable , when we compare.
> I must have to admit , that regarding chokes, I can not tell any
difference ,
> between the Toroids or C/EI. (In fact I allmost belive the Toroids are a
tiny bit,
> better here.?)
> But toroids as output-transformers , is to me a dead end.
> Toroids tends to hesitate to deliver the currents.(That might be why ,
they seems to
>
> be a little better as chokes ?)
>
> - Sincerely Kurt
>
=========================================================================
From: Kurt Steffensen <solvin-aurum@get2net.dk>
Subject: Re: [JN] Wanted: Large Current Power transformers
Date: Mon, 01 Feb 1999 18:31:47 +0100
Source: Sound Digest Archive v02.n019
Dear Chris , and all other interested.
Chris Beck skrev:
> Does anyone have mathematical proof or even theory why such large, low impedance
> supplies make such a difference to our amps?
Yes, I do, to the degree that mathematics proofs anything in this matter.
The delta current that is drawn from the amplifier , changes the voltage to be
supplied to the same , with the value of the Z-out in the PSU. (dI x Z )
If the delta current is 100mA , and the Z of the transformer is say 300 Ohm ,
then the voltage change is at least 60 Volts.(The small iron mass ads to this)
As all these happens very fast , but fully within the audio range , these changes ,
appears as "ringning" or fast unpredictable oscillations.(Not visuable with sines)
Further is influence the dynamics , and power output of the system.
The ringning is mainly due to the reaction between the Z of the transformer ,
and the capacity of the capacitors.
Low-Z , transformers and low DC-Ohm chokes, and LOTS of uF´s , makes
the amplifier more , dynamic ,steady and lowers the DYNAMIC distortion.
It simply sounds a lot better , the lower the impedance , the PSU can do.
The regulated ones surely are the best , but one can do good , with big
transformers,
chokes and capacitors.
You really do not need the mathematical proof , Chris, you can hear it instantly ,
if you try to compare.
Like our good Bill (Perkins) , I do preferes the EI or C-cores.
But the difference is not big.... It is just audiable , when we compare.
I must have to admit , that regarding chokes, I can not tell any difference ,
between the Toroids or C/EI. (In fact I allmost belive the Toroids are a tiny bit,
better here.?)
But toroids as output-transformers , is to me a dead end.
Toroids tends to hesitate to deliver the currents.(That might be why , they seems to
be a little better as chokes ?)
- - Sincerely Kurt
=========================================================================
From: dslagle@earthlink.net (dave slagle)
Subject: Re: [JN] Wanted: Large Current Power transformers
Date: Mon, 1 Feb 1999 14:17:30 -0500
Source: Sound Digest Archive v02.n020
my clip lead fore-father stated some wise words...
we all have to realize that what we are doing is merely a matter of taste
and proiorities...
the biggest positive improvements I have heard in my system center around
the implamentation of power supplies. I have yet to attepmpt regulated,
but the "low dcr" approach in conjunction with MV rectafiers has led me in
a direction I like.
other things that have pushed me in that direction are IT's, and nickel
trannies.
other things that others concentrate on like silver wire, soldered
connections, and tube choice, have not been a priority of mine as of late,
since changing these seems to give me different sound, but not improved
sound. they all seemed to be lateral moves.
one of the best compliments I ever recieved was that I have worked my
system to the point of non-function... (apparently due to my lack of
engineering skills)
if you don't agree with what I say, don't discount it... try it... if you
don't like it... fine we like different things... and you never have to
listen to me again.
there are certain members of the community who have lead me astray with
their advice... I now know not to listen to them... not because they were
wrong, but because we have different tastes.
all it takes is a little time, and you will find people who have similar
tastes, and you can follow them to your dream system...
this whole thing started with someone putting trust in herb's assertation
that a bigass power trannie helps... and someone wanted to put faith in
herb's experiences...
of course lines must be drawn somwhere... but I suggest you should draw
your own lines based on your own experiences.
if you have limited experiences... you have to put your trust in someone...
I was lucky to find some great people here to follow...
dave
=========================================================================
From: Roscoe Primrose <roscoe@aiko.com>
Subject: Re: [JN] Wanted: Large Current Power transformers
Date: Mon, 01 Feb 1999 21:20:00 -0500
Source: Sound Digest Archive v02.n020
Torbjørn Lien wrote:
>
> Hello,-
> Seems that there is a groving consensus of the PSU consept described by
> lotsa' iron and *small* caps,-this then to lead
> to the most musically, most artistically resolving, to the
> most natural "speed" of sound ???......
>
> I must say that I'm puzzeled,-this approach goes against all
> my own experiences,-so I really wonder why,-
>
> Anyone?
>
> In my designs I have found the contrary to be true,-and there
> has never been, IMHO any contest whatsoever .....
I agree, 100%!
>
> There have been several tries of explaining how big caps *slow*
> down the sound of an amp,-so far I'll say that none of them
> have been understandable to me....Just think of this: *Any* R-C
> or LC network between x-former and amp is an intrinsically slow
> device,-*much* slower than music itself.
Exactly. Any musical transient that causes the load on the PS to
increase dramatically causes the increase in load AT SOME AF FREQUENCY
based on the musical signal. At that AF frequency, the impeadance of
the low dcr choke is 10s to 1000s of times the dcr anyway...
Snip...
>
> If the quest is for *real* dynamics, unconditionally stable operation
> and a fast recovery , one simply has to *keep all DC
> working points as stable as possible*. Simple as that. Meaning adequate
> iron to load caps, and as few caps as possible to
> *shift* the working points around. Meaning no cathode bias.
Unless, or course, you use big, unmoveable caps on the cathode bias
too... Of course, you may run into sonic problems with Cks that big
being unavailable in desirable dielectrics.
> No R-C coupling to any tube that can draw grid current.....
> And meaning *big* "unmoveable" caps in the PSU.
>
> On the other hand, I've found that with small PSU caps, cap-coupling to
> output tubes, and cathode bias,-the working points,
> especially under heavy loads are prone to wander all over the
> place...
Well, for instrument amps, this can be a problem. I try to build the
amp/speaker interface at home such that the amps are never under heavy
loads.
Snip...
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: "=?ISO-8859-1?Q?Torbj=F8rn_Lien?=" <mdrivekl@online.no>
Subject: Re: [JN] Wanted: Large Current Power transformers
Date: Tue, 2 Feb 1999 00:01:20 +0100
Source: Sound Digest Archive v02.n020
Hello,-
Seems that there is a groving consensus of the PSU consept described by
lotsa' iron and *small* caps,-this then to lead
to the most musically, most artistically resolving, to the
most natural "speed" of sound ???......
I must say that I'm puzzeled,-this approach goes against all
my own experiences,-so I really wonder why,-
Anyone?
In my designs I have found the contrary to be true,-and there
has never been, IMHO any contest whatsoever .....
There have been several tries of explaining how big caps *slow*
down the sound of an amp,-so far I'll say that none of them
have been understandable to me....Just think of this: *Any* R-C
or LC network between x-former and amp is an intrinsically slow
device,-*much* slower than music itself. So, if recovery is of consern,
I'd say it's to slow anyway,-meaning that the only sensible way to get
unwanted (I guess it still is?) ripple
down is to supress it with *big* caps...
I have worked with and on several amps and gathered insight
especially when working on amps for electric guitars and basses:
Amps like these are working under far heavier and more difficult
situations than amps for home audio ever will. The dynamic of
the input signal isn't restricted, as in canned music. Or,-it can be
the opposit situation too: Often there is a constant balancing act,-not
to drive the amp into clipping or saturation,-
Yes I know,-These are really two different worlds,-but still...
What is "subtle changes" in a home-audio amp really show up in
a musical-instrument amp because of the latter ones far more demanding
usage.
If the quest is for *real* dynamics, unconditionally stable operation
and a fast recovery , one simply has to *keep all DC
working points as stable as possible*. Simple as that. Meaning adequate
iron to load caps, and as few caps as possible to
*shift* the working points around. Meaning no cathode bias.
No R-C coupling to any tube that can draw grid current.....
And meaning *big* "unmoveable" caps in the PSU.
On the other hand, I've found that with small PSU caps, cap-coupling to
output tubes, and cathode bias,-the working points,
especially under heavy loads are prone to wander all over the
place...This gives to my ears a dynamically challenged sound,
anemic,flat, but sometimes "falsely detailed", I guess due to subtle
compression action..I don't want this. Canned music is
compressed enough as it is!
When I make PSU's for my designs, I'm really conserned with
just two things:
To try to rectify the AC with as little noise induced in the
mains-tranny and gnd. as possible, *to supress common mode
noise*. Common mode noise is really bad. Yet no one seems to
bother!!...
Common mode noise makes noise currents run in the gnd.-path between the
various amps or signal sources,-and as no gnd. path
is of zero resistance, *a noise signal is develloped that is put
in series with your signal to be amplified*: Supress the common
mode noise and get rid of the subtle grunge in your sound....
Number two: I use *big* caps to make unmovable, diff-mode noise
free supply voltages. Now,-if the supply voltage is *stable* deep
into the clipping region,-how can it be "slow" ??
Regards,
Torbjoern Lien
> From: Kurt Steffensen <solvin-aurum@get2net.dk>
> As all these happens very fast , but fully within the audio range ,
these changes ,
> appears as "ringning" or fast unpredictable oscillations.(Not
visuable with sines)
> Further is influence the dynamics , and power output of the system.
> The ringning is mainly due to the reaction between the Z of the
transformer ,
> and the capacity of the capacitors.
>
> Low-Z , transformers and low DC-Ohm chokes, and LOTS of uF´s , makes
> the amplifier more , dynamic ,steady and lowers the DYNAMIC
distortion.
>
Yeppyepp !!
=========================================================================
From: Joe Pledger <doodle@navicom.com>
Subject: Re: [JN] Wanted: Large Current Power transformers
Date: Mon, 01 Feb 1999 21:46:52 -0800
Source: Sound Digest Archive v02.n021
Dave Slagle wrote:
>
> >Exactly. Any musical transient that causes the load on the PS to
> >increase dramatically causes the increase in load AT SOME AF FREQUENCY
Hi Dave,
Sounds reasonable, everything has a frequency!
> >based on the musical signal. At that AF frequency, the impeadance of
> >the low dcr choke is 10s to 1000s of times the dcr anyway...
-Well what I've ended up with is a little high on the dcr
spectrum...but the junk box being what it is...!
> OK I may be in a bit over my head here, but aren't we talking about
> electrons and ohms law here???
>
> I do not see where the frequency comes into it.... I thought the idea of
> the chokes reactance was to hinder the AC signals, yet provide an easy path
> for DC, and the caps were to deal with the transient power needs.
>
> when the transient happens at 1K the power supply doesn't supply a 1K signal
> to replace it... it just sends some more electrons down the pipe (well...
> sucks them up) and the dcr of the choke is what rules the electrons
> domain... not the impedance
>
> in one sense, ideally we want a large bank of capacitors to supply infinite
> power... but we have to remember that every electron we take from a cap has
> to be replaced... and the higher the DCR the harder it is to replace.
>
> so if we want that rock solid supply via large caps I would think we would
> still want a low impedance replacement mechanism... as soon as a cap gets
> discharged... it wants to be charged... so the big transient that instantly
> lowers the resivoir... immediately commands a huge amount from the charging
> circuit if you will... and we are talking current here... if the PT cannot
> provide it... it will sag and that sag will be voltage which tosses the
> rock solid supply out the window.
>
> I guess the problem I have with large amounts of capacitence involves the
> idea that I do not like the sound of the caps required to get these large
> values.
>
> I have always preferred lower amounts of oil caps to any other type I have
> tried... they seem to do less damage to the sound.
>
> Of course I have not tried every cap out there... but I would rather have
> 50mics of oil caps in my PS than 50 mics of elna's or solens... I also
> believe that 50 mics of solens has the same signature as 200 mics of
> solens... they just seem to add something annoying to the sound.
>
> Logistically going for the mega oil-cap supply is a possibility, but my
> limited experiences... and listening to people whose ears I trust have me
> comfortable with just enough oil caps in my filters to get the ripple to a
> bearable level.... and doubling or quadripleing this value has showed me no
> reward thus far... someday maybe 10X or 100X may be tried, but for now I am
> happy.
>
> so maybe the big cap vs. small cap group merely have different tastes and
> choose different compromises... my current compromise being smaller amounts
> of oil caps.
- Perhaps so...back to the junk box, I'm tryin a few of those
"one-time-purchase" caps from Doc B' dumpster dive...36uf, 3.6KVDC
"K-Film" caps and a couple 6uf,600VDC oil caps. So, where does the
optimun mix come in? I've seen high valuse caps followed by low
value...whatever...and the other way around. Is there a frequency
handicap involved with using same value caps throughout a PS? Some of
this was covered before, but I can't find it. Just how are we shaping
the output bandwith by cap selection in the PS?
Thanks for the bandwidth,
Joe Pledger
> I guess this is just a different road... eventually we may all get to the
> same point, I guess the key is to get there your own way, and enjoy the
> music while you do it.
>
> as for the original poster... I say go for the toroid... the specs and price
> and my personal results with using them make a good compromise... If you try
> them and they suck... you will know to not listen to me anymore....
>
> the nice low DCR power supply, and those permalloy outputs should make a
> beautiful sounding amp! or at least one that suits my tastes well.
>
>
> dave
=========================================================================
From: Grover Gardner <groverg@postoffice.att.net>
Subject: Re: [JN] Wanted: Large Current Power transformers
Date: Mon, 1 Feb 1999 23:15:01 -0500
Source: Sound Digest Archive v02.n021
At 12:01 AM +0100 2/2/99, Torbjørn Lien wrote:
>If the quest is for *real* dynamics, unconditionally stable operation
>and a fast recovery , one simply has to *keep all DC
>working points as stable as possible*. Simple as that. Meaning adequate
>iron to load caps, and as few caps as possible to
>*shift* the working points around. Meaning no cathode bias.
>No R-C coupling to any tube that can draw grid current.....
>And meaning *big* "unmoveable" caps in the PSU.
I'm definitely in agreement here, brother.
Grover Gardner
groverg@postoffice.att.net
=========================================================================
From: "Dave Slagle" <dslagle@earthlink.net>
Subject: Re: [JN] Wanted: Large Current Power transformers
Date: Mon, 01 Feb 1999 23:21:24 -0500
Source: Sound Digest Archive v02.n021
>Exactly. Any musical transient that causes the load on the PS to
>increase dramatically causes the increase in load AT SOME AF FREQUENCY
>based on the musical signal. At that AF frequency, the impeadance of
>the low dcr choke is 10s to 1000s of times the dcr anyway...
OK I may be in a bit over my head here, but aren't we talking about
electrons and ohms law here???
I do not see where the frequency comes into it.... I thought the idea of
the chokes reactance was to hinder the AC signals, yet provide an easy path
for DC, and the caps were to deal with the transient power needs.
when the transient happens at 1K the power supply doesn't supply a 1K signal
to replace it... it just sends some more electrons down the pipe (well...
sucks them up) and the dcr of the choke is what rules the electrons
domain... not the impedance
in one sense, ideally we want a large bank of capacitors to supply infinite
power... but we have to remember that every electron we take from a cap has
to be replaced... and the higher the DCR the harder it is to replace.
so if we want that rock solid supply via large caps I would think we would
still want a low impedance replacement mechanism... as soon as a cap gets
discharged... it wants to be charged... so the big transient that instantly
lowers the resivoir... immediately commands a huge amount from the charging
circuit if you will... and we are talking current here... if the PT cannot
provide it... it will sag and that sag will be voltage which tosses the
rock solid supply out the window.
I guess the problem I have with large amounts of capacitence involves the
idea that I do not like the sound of the caps required to get these large
values.
I have always preferred lower amounts of oil caps to any other type I have
tried... they seem to do less damage to the sound.
Of course I have not tried every cap out there... but I would rather have
50mics of oil caps in my PS than 50 mics of elna's or solens... I also
believe that 50 mics of solens has the same signature as 200 mics of
solens... they just seem to add something annoying to the sound.
Logistically going for the mega oil-cap supply is a possibility, but my
limited experiences... and listening to people whose ears I trust have me
comfortable with just enough oil caps in my filters to get the ripple to a
bearable level.... and doubling or quadripleing this value has showed me no
reward thus far... someday maybe 10X or 100X may be tried, but for now I am
happy.
so maybe the big cap vs. small cap group merely have different tastes and
choose different compromises... my current compromise being smaller amounts
of oil caps.
I guess this is just a different road... eventually we may all get to the
same point, I guess the key is to get there your own way, and enjoy the
music while you do it.
as for the original poster... I say go for the toroid... the specs and price
and my personal results with using them make a good compromise... If you try
them and they suck... you will know to not listen to me anymore....
the nice low DCR power supply, and those permalloy outputs should make a
beautiful sounding amp! or at least one that suits my tastes well.
dave
=========================================================================
From: Roscoe Primrose <roscoe@aiko.com>
Subject: Re: [JN] Wanted: Large Current Power transformers
Date: Mon, 01 Feb 1999 23:58:07 -0500
Source: Sound Digest Archive v02.n021
Dave Slagle wrote:
>
> >Exactly. Any musical transient that causes the load on the PS to
> >increase dramatically causes the increase in load AT SOME AF FREQUENCY
> >based on the musical signal. At that AF frequency, the impeadance of
> >the low dcr choke is 10s to 1000s of times the dcr anyway...
>
> OK I may be in a bit over my head here, but aren't we talking about
> electrons and ohms law here???
>
> I do not see where the frequency comes into it.... I thought the idea of
> the chokes reactance was to hinder the AC signals, yet provide an easy path
> for DC, and the caps were to deal with the transient power needs.
>
> when the transient happens at 1K the power supply doesn't supply a 1K signal
> to replace it... it just sends some more electrons down the pipe (well...
> sucks them up) and the dcr of the choke is what rules the electrons
> domain... not the impedance
>
Ah, but in order to recharge (or, maintain charge in) the cap in
response to the 1K transient, we have to change the current through the
choke (which chokes don't like) at a frequency of 1K, or the voltage
falls if we can't recharge it fast/soon enough. In order to maintain
constant voltage at all times, we have to respond as quickly to changes
in demand as those changes....
> in one sense, ideally we want a large bank of capacitors to supply infinite
> power... but we have to remember that every electron we take from a cap has
> to be replaced... and the higher the DCR the harder it is to replace.
As explained above, for the transient condition it's the reactance we
need to worry about, since it's generally some orders of magnitude
greater than the dc resistance.
>
> so if we want that rock solid supply via large caps I would think we would
> still want a low impedance replacement mechanism... as soon as a cap gets
> discharged... it wants to be charged... so the big transient that instantly
> lowers the resivoir... immediately commands a huge amount from the charging
> circuit if you will... and we are talking current here...
Indeed, we are talking current, but you can't instantly change the
current through an inductor without developing infinite voltage across
the inductor.
> if the PT cannot
> provide it... it will sag and that sag will be voltage which tosses the
> rock solid supply out the window.
>
> I guess the problem I have with large amounts of capacitence involves the
> idea that I do not like the sound of the caps required to get these large
> values.
>
That's a whole nother issue....
Snip...
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: Steve Berger <aprilsound@earthlink.net>
Subject: Re: [JN] Wanted: Large Current Power transformers
Date: Tue, 02 Feb 1999 03:26:41 -0500
Source: Sound Digest Archive v02.n021
Hello again Torbjorn:
All I can say is, be unreasonable for a moment and try what we are
talking about. Use LOW DCR chokes and small film and oil caps! Just try
it. Then lets talk.
Yours truly,
Steve
- --
Steve Berger <http://home.earthlink.net/~aprilsound/>
=========================================================================
From: "blackie" <blackie@mail.infohouse.com>
Subject: Re: [JN] Wanted: Large Current Power transformers
Date: Tue, 2 Feb 1999 08:08:22 +0000
Source: Sound Digest Archive v02.n021
> From: "Torbjorn Lien" <mdrivekl@online.no>
> To: "Kurt Steffensen" <solvin-aurum@get2net.dk>,
> "Chris Beck" <n9zes@execpc.com>
> Cc: "PEARL Cust Serv" <custserv@pearl-hifi.com>, <sound@lists.io.com>
> Subject: Re: [JN] Wanted: Large Current Power transformers
> Date: Tue, 2 Feb 1999 00:01:20 +0100
> Hello,-
> Seems that there is a groving consensus of the PSU consept described by
> lotsa' iron and *small* caps,-this then to lead
> to the most musically, most artistically resolving, to the
> most natural "speed" of sound ???......
>
> I must say that I'm puzzeled,-this approach goes against all
> my own experiences,-so I really wonder why,-
> I have worked with and on several amps and gathered insight
> especially when working on amps for electric guitars and basses:
> Amps like these are working under far heavier and more difficult
> situations than amps for home audio ever will. The dynamic of
> the input signal isn't restricted, as in canned music. Or,-it can be
> the opposit situation too: Often there is a constant balancing act,-not
> to drive the amp into clipping or saturation,-
> Yes I know,-These are really two different worlds,-but still...
> What is "subtle changes" in a home-audio amp really show up in
> a musical-instrument amp because of the latter ones far more demanding
> usage.
Hmmmm...can't resist this one
This is an interesting comparison...basically the old accuracy vs.
pleasing sound schism
the most popular guitar amp circuits are the old school stuff w/
small caps, small or no chokes, cathode bias, tube rectification.
Pleasing distortion and warm clean sound are the benchmarks, strictly
ear and taste driven...BTW all guitar amp speakers start to roll off
around 5-6k...this is the classic sound.
Most guitar players HATE fast, accurate sounding solid state
amps...too unforgiving, powerful and annoying sounding. Bass players
tend to like more powerful, accurate sounding tube amps like SVT, but
who wants to carry 100 lbs to every gig? They settle for SS...
Ye gads, I cannot tell you how many butchered (added power supply
capacitance and SS rectifiers) Fenders I have restored...
Let's face it, all amps clip, so IMHO why have ugly clipping? The
concept of accuracy in a music reproduction device is something of a
joke...every amp and speaker has a signature...why not a pleasing
one?
I sat down w/ jc and we designed and built an amp that had excellent
numbers using 6550's, hexfreds, ultralinear, big caps, etc. Guess
what? It was no FUN to listen to!!! Pointless, sonically. Went
triode, no NFB, etc. and made an amp that has killer detail but
sounds lively, fun, makes you wanna do the Pee Wee Herman in the
nude!!!
So, like the Wisconsin Clipper and Jazzman Berger sez:
try it, you'll like it!!
da dot da da da da dot da
da dot da da da da dah!
blackie
blackie@tubesville.com
www.tubesville.com
=========================================================================
From: Patrick Currie <tubesguy@chorus.net>
Subject: Re: [JN] Wanted: Large Current Power transformers
Date: Mon, 1 Feb 1999 23:01:33 -0600
Source: Sound Digest Archive v02.n022
> Common mode noise is really bad. Yet no one seems to
>bother!!...
>Common mode noise makes noise currents run in the gnd.-path between the
>various amps or signal sources,-and as no gnd. path
>is of zero resistance, *a noise signal is develloped that is put
>in series with your signal to be amplified*: Supress the common
>mode noise and get rid of the subtle grunge in your sound....
>Regards,
>Torbjoern Lien
Torbjoern -
Come to VSAC next year and speak with "Buddha" Camille. He is concerned
about the same issues, and his PS was a major improvement in my 845 amp. -
Pat
=========================================================================
From: "Chris Beck" <cbeck@brewercompany.com>
Subject: Re: [JN] Wanted: Large Current Power transformers
Date: Tue, 2 Feb 1999 07:23:30 -0600
Source: Sound Digest Archive v02.n022
Dave,
Regarding the Solens. These are supposed to be ultra low ESR, correct? Is
it feasible that the "annoying" sound that people say these produce is
caused by undamped ultrasonic ringing? I've seen schematics where people
put resistors in series with the caps, which goes against my idea of low
ESR, then. But, considering caps and inductors constitute a resonant tank
circuit at a particular frequency, would it not make sense that a little
resistance would damp this out? I think it's called filter bounce? Maybe
that's why people like those old paper/oil caps. They are just lossy
enough to smooth things out, but the dielectric doesn't screw up the sound
like a electrolytic.
Just a thought....
Chris Beck
See my web page at: http://www.execpc.com/~n9zes/index.htm
- ----------
> From: Dave Slagle <dslagle@earthlink.net>
> To: sound@lists.io.com
> Subject: Re: [JN] Wanted: Large Current Power transformers
> Date: Monday, February 01, 1999 10:21 PM
>
>
> >Exactly. Any musical transient that causes the load on the PS to
> >increase dramatically causes the increase in load AT SOME AF FREQUENCY
> >based on the musical signal. At that AF frequency, the impeadance of
> >the low dcr choke is 10s to 1000s of times the dcr anyway...
>
> OK I may be in a bit over my head here, but aren't we talking about
> electrons and ohms law here???
>
> I do not see where the frequency comes into it.... I thought the idea of
> the chokes reactance was to hinder the AC signals, yet provide an easy
path
> for DC, and the caps were to deal with the transient power needs.
>
> when the transient happens at 1K the power supply doesn't supply a 1K
signal
> to replace it... it just sends some more electrons down the pipe (well...
> sucks them up) and the dcr of the choke is what rules the electrons
> domain... not the impedance
>
> in one sense, ideally we want a large bank of capacitors to supply
infinite
> power... but we have to remember that every electron we take from a cap
has
> to be replaced... and the higher the DCR the harder it is to replace.
>
> so if we want that rock solid supply via large caps I would think we
would
> still want a low impedance replacement mechanism... as soon as a cap gets
> discharged... it wants to be charged... so the big transient that
instantly
> lowers the resivoir... immediately commands a huge amount from the
charging
> circuit if you will... and we are talking current here... if the PT
cannot
> provide it... it will sag and that sag will be voltage which tosses the
> rock solid supply out the window.
>
> I guess the problem I have with large amounts of capacitence involves the
> idea that I do not like the sound of the caps required to get these large
> values.
>
> I have always preferred lower amounts of oil caps to any other type I
have
> tried... they seem to do less damage to the sound.
>
> Of course I have not tried every cap out there... but I would rather have
> 50mics of oil caps in my PS than 50 mics of elna's or solens... I also
> believe that 50 mics of solens has the same signature as 200 mics of
> solens... they just seem to add something annoying to the sound.
>
> Logistically going for the mega oil-cap supply is a possibility, but my
> limited experiences... and listening to people whose ears I trust have me
> comfortable with just enough oil caps in my filters to get the ripple to
a
> bearable level.... and doubling or quadripleing this value has showed me
no
> reward thus far... someday maybe 10X or 100X may be tried, but for now I
am
> happy.
>
> so maybe the big cap vs. small cap group merely have different tastes and
> choose different compromises... my current compromise being smaller
amounts
> of oil caps.
>
> I guess this is just a different road... eventually we may all get to the
> same point, I guess the key is to get there your own way, and enjoy the
> music while you do it.
>
> as for the original poster... I say go for the toroid... the specs and
price
> and my personal results with using them make a good compromise... If you
try
> them and they suck... you will know to not listen to me anymore....
>
> the nice low DCR power supply, and those permalloy outputs should make a
> beautiful sounding amp! or at least one that suits my tastes well.
>
>
> dave
>
>
>
=========================================================================
From: dslagle@earthlink.net (dave slagle)
Subject: Re: [JN] Wanted: Large Current Power transformers
Date: Tue, 2 Feb 1999 09:12:06 -0500
Source: Sound Digest Archive v02.n022
>Dave,
>
>Regarding the Solens. These are supposed to be ultra low ESR, correct? Is
>it feasible that the "annoying" sound that people say these produce is
>caused by undamped ultrasonic ringing?
or how about undamped mechanical ringing???
I have heard it posed that oil caps are not dull, all other caps ring like
a bell...
I have heard if you cut open many of the motor start caps, they are a solen
like cap in a can of oil, yet they still do not have the solen-like
sound... could it just be the oil mechanically damping the cap???
many people like the "detail" of a cap but often I feel the added detail of
many caps is not actually the cap revealing some hidden info, but it adding
some.
it just becomes a cup is 1/2 empty vs 1/2 full and my viewpoint at the
moment are oil caps do not remove any info... if they sound dull in your
system you should look elsewhere for a solution...
I have no problems choosing parts for their sonic signature, often when my
system gets a little dull sounding, I'll toss a solen in... it does fine
for a day or two, but then starts to annoy the hell out of me... so back
goes the oil.
>I've seen schematics where people
>put resistors in series with the caps, which goes agains