Sound Practices Mailing List Files - Volume 1
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From: Rhthatcher@ra.rockwell.com
Subject: 9001 tube
Date: Thu, 23 Apr 1998 16:00:20 -0400
Source: Sound Digest Archive v01.n260
what the heck is a 9001? i just got one thrown in with a tube order...
fyi, i just got an order from kirk cline 336-379-7197
extremely fast, threw in an extra 2 tubes. great prices, too. i am not
affiliated with him,
he just surprised me with the great service!
randy
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From: Simon Busbridge <S.C.Busbridge@bton.ac.uk>
Subject: Re: 9001 tube
Date: Fri, 24 Apr 1998 07:44:15 +0100 (BST)
Source: Sound Digest Archive v01.n261
Hi Randy,
The 9001 is a small UHF pentode with a B7G base. It is equivalent to the
British EF95 which was popular as an rf amplifier. It is also similar to
the 954 acorn valve. I've always fancied trying this and the 9002 (B7G
triode) in a phono stage, but never gotten around to it.
Regards
Simon
Dr Simon Busbridge
Department of Mechanical and Manufacturing Engineering
University of Brighton
Lewes Road
Moulsecoomb
Brighton BN2 4GJ
UNITED KINGDOM
Tel: 0044 (0)1273 642542
Fax: 0044 (0)1273 642327
e-mail: s.c.busbridge@bton.ac.uk
"..biology is what you do when you don't have the maths for real
science.." (sliders)
On Thu, 23 Apr 1998 Rhthatcher@ra.rockwell.com wrote:
> what the heck is a 9001? i just got one thrown in with a tube order...
>
>
> fyi, i just got an order from kirk cline 336-379-7197
>
> extremely fast, threw in an extra 2 tubes. great prices, too. i am not
> affiliated with him,
> he just surprised me with the great service!
>
> randy
>
>
>
=========================================================================
From: Bob Danielak <rdaniela@ew.lmms.lmco.com>
Subject: 9/19 what i did this weekend
Date: Thu, 25 Sep 1997 15:42:08 -0400
Source: Sound Digest Archive v01.n043
hi gang,
late again. just got back on-line after the office move from
princeton, nj to newtown, pa.
my drive just went from 1hr to almost 1 1/2 hr.
i must definitely finish that automotive tube amp, soon...
not much time spent on building this w/e .
one thing i did was retrofit a pair of 71A's into my stereo
1626 amp. they put out a similar power level ( <1W) and use
about the same load, so i figured
that the DHT 71A would perform/sound much better than the IHT 1626.
i guess i was wrong...
the 71A was pretty nice (looked real sharp, too with those
"inverted W" filaments peeking thru the top).
but it sounded a bit strained. not as lively and "fun" as the 1626.
it is possible that this is because the 1626 is an RF power triode.
it may have been designed to handle overdrive/grid current/A2
operation. so it either provides some additional power
or at least overloads more gracefully
...?
also played a bit more with "absolute phase" experiments.
i tried it on the 1626 amp, 71A amp, and my pp2a3 amp.
playing the same source material: steve miller band, stones,
new age stuff "coming full circle?"
in all cases, opposite phase (black-to-red,red-to-black) sounded
better to my ears. seemed punchier and image seemed more spread out
and higher above the speakers.
my brother seemed to think the bass was cleaner in normal phase.
but overall sounded better in opposite phase.
then later, he felt that normal phase sounded better with
some miles and coltrane cd's .
boy this is confusing. i'm getting tired of this experiment
very rapidly.
speaking with johannes, i thought i had it knocked. then
by experiments at home were contraditory.
thenn i thought i had an explanation for why my results were different
(clipping the driver input emphasizes the opposite half-cycle).
so this effect may invert from low level to high level...
dave slagle wondered if his back loaded big-fun horns had anything to
do with this effect.
(negative cycle pushed air out of the back of the horn)
then i seem to get differing results with different albums...
not sure i care anymore ;)
yeah, i know, shut up and listen!
finally getting back to the big power supply for the pp3cx300
amp. should have 950V on tap this weekend.
going to try it out on the amp i've already built, but going to
do a new chassis to house much bigger fans.
eack tube is going to idle at about 100W with max signal dissipation
near 200W ea. !!!!
keep ya posted!
bob.d.
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From: Bob Danielak <rdaniela@ew.lmms.lmco.com>
Subject: 9/27 what i did this weekend
Date: Mon, 29 Sep 1997 15:52:02 -0400
Source: Sound Digest Archive v01.n047
hi guys,
one little tidbit to report from this weekend.
still enjoying my se stereo 1626 amp. having a few more 1626
on hand, i had an idea:
i built a stereo push pull 5687 amp a while back using two 5687
per channel and a couple of AES little nickle IT's driven by a single
12au7. it ran on a 260V supply and fit into a 8" x 10" x 2" chassis.
i wonder if i could convert it to push-pull 1626 ?!!!
of course i could!
rip out (literally) the 9-pin sockets and a few parts.
punch out octal holes (spaced out a little for the 1626's "hips" ).
mount new sockets. new cathode bias network and i was done.
biased it about the same as my SE 1626 amp for two and a half
class A watts. sounds pretty good. nice imaging. better than the
5687 version (sorta expected).
unfortunately, nowhere near the se 1626 version.
a bit louder (sorta expected), not quite as punchy,
a little brighter (maybe annoyingly so).
could use a bit more tweaking or maybe a totally different driver.
going to have to dig up that thread on working with the AES
IT (proper hook-up and loading, etc).
could also re-work my original differential input push-pull 5687
amp. i decided to work with the IT coupled version because
i couldn't think of a suitable input/driver stage that would
split phase and provide a gain of >30 with a single stage.
a 5695 gives me <20X in a diff amp, 12ax7 does about 40x
but is a bit mushy as a driver.
even considered split load preceded by a simple gain stage,
but that would be two stages, and i'm pretty sure the output
overloads on peaks, so don't like the assymetical drive impedance.
i also remembered the nice low level detail that i noticed
(even with this cheap IT) when i first tried the IT.
i promised myself that the next pp amp i build would use IT
for phase splitting. i though it would be a good match for the
1626 sound. maybe i should pursue this one a bit further.
i don't know. the se version seems hard to beat.
bob.d.
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From: Guido Tent <gtent@ehv.sc.philips.com>
Subject: 9710 cabinet
Date: Mon, 15 Sep 1997 12:10:51 +0200
Source: Sound Digest Archive v01.n023
Bert,
Ik heb op je pagina rondgekeken, en heb niets expliciets gevonden over de
9710 unit van Philips. Heeft iemand bouwtekeningen / ervaring met een hoorn
(direct stralend graag) met deze full-range unit ?
Hoi,
- -
Guido
" 640K ought to be enough for anybody" , Bill Gates, 1981
Disclaimer: The opinions expressed herin are my personal ones and do not in
any way reflect opinions or policies of my employer.
Guido Tent
Engineer Electro Magnetic Compatibility
Philips Semiconductors Systems Laboratory Eindhoven (PS-SLE)
Building BE303, (Hurksestraat 19)
P.O.Box 218, 5600MD Eindhoven, The Netherlands
Phone: +31-40-27 24553
fax : +31-40-27 22764
- - Let's make things better ! -
E-mail: guido.tent@ehv. sc.philips.com
Seri : gtent@nlsce1
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From: Grego Sanguinetti <grego@latticesemi.com>
Subject: Re: 9710 cabinet
Date: Mon, 15 Sep 1997 14:24:13 -0700 (PDT)
Source: Sound Digest Archive v01.n024
On Mon, 15 Sep 1997, Andre Jute wrote:
> Kerels,
>
> Doen julle vreemde tale in privaat. Die res wat net Engels het sal paranoid
> raak!
Yeah, you guys could be talking about sending us all Bose's
for Christmas or something...
> Andre
> Met apologie vir my swak Hollands
Not to mention....
> >Ik heb op je pagina rondgekeken, en heb niets expliciets gevonden over de
> >9710 unit van Philips. Heeft iemand bouwtekeningen / ervaring met een hoorn
> >(direct stralend graag) met deze full-range unit ?
> >
> >Hoi,
> >-
> >Guido
Pass on those and find some good Altecs B^)
- -grego
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From: andre@indigo.ie (Andre Jute)
Subject: Re: 9710 cabinet
Date: Mon, 15 Sep 1997 16:47:56 +0100 (BST)
Source: Sound Digest Archive v01.n024
Kerels,
Doen julle vreemde tale in privaat. Die res wat net Engels het sal paranoid
raak!
Andre
Met apologie vir my swak Hollands
At 12:10 pm 15/9/97, Guido Tent wrote:
>Bert,
>
>Ik heb op je pagina rondgekeken, en heb niets expliciets gevonden over de
>9710 unit van Philips. Heeft iemand bouwtekeningen / ervaring met een hoorn
>(direct stralend graag) met deze full-range unit ?
>
>Hoi,
>-
>Guido
>" 640K ought to be enough for anybody" , Bill Gates, 1981
>
>Disclaimer: The opinions expressed herin are my personal ones and do not in
>any way reflect opinions or policies of my employer.
>
>Guido Tent
>Engineer Electro Magnetic Compatibility
>Philips Semiconductors Systems Laboratory Eindhoven (PS-SLE)
>Building BE303, (Hurksestraat 19)
>P.O.Box 218, 5600MD Eindhoven, The Netherlands
>Phone: +31-40-27 24553
>fax : +31-40-27 22764
>
>- Let's make things better ! -
>
>E-mail: guido.tent@ehv. sc.philips.com
>Seri : gtent@nlsce1
>
Andre Jute
andre@indigo.ie
Communication Jute
the main index to the pages we support for lovers of classical music, for
writers, and for audiophiles is at
http://www.foundmark.com/ComJute/ComJuteF1.html
=========================================================================
From: andre@indigo.ie (Andre Jute)
Subject: Re: 9710 cabinet
Date: Tue, 16 Sep 1997 03:50:32 +0100 (BST)
Source: Sound Digest Archive v01.n024
Since the prediction has come true, I supply a translation:
At 2:24 pm 15/9/97, Grego Sanguinetti wrote:
>On Mon, 15 Sep 1997, Andre Jute wrote:
>
>> Kerels,
Fellows,
>> Doen julle vreemde tale in privaat. Die res wat net Engels het sal paranoid
>> raak!
Do your talking in foreign languages in private. The rest who have only
English will become paranoid!
>Yeah, you guys could be talking about sending us all Bose's
>for Christmas or something...
((((((I told you it would happen! <G>))))
>> Andre
>> Met apologie vir my swak Hollands
With apologies for my poor Dutch.
>Not to mention....
>
>> >Ik heb op je pagina rondgekeken, en heb niets expliciets gevonden over de
>> >9710 unit van Philips. Heeft iemand bouwtekeningen / ervaring met een hoorn
>> >(direct stralend graag) met deze full-range unit ?
I have looked around on your page, and found nothing explicit about the
9710 Philips unit (driver). Does anyone have drawings and
instructions/experience with a horn (preferably directly radiating) with
this full-range unit?
>> >Hoi,
Yo!
- -
>> >Guido
>
>Pass on those and find some good Altecs B^)
Buy mine! (Grego's)
>-grego
Andre
Andre Jute
andre@indigo.ie
Communication Jute
the main index to the pages we support for lovers of classical music, for
writers, and for audiophiles is at
http://www.foundmark.com/ComJute/ComJuteF1.html
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From: Thomas.Eberhard@labmed.ki.se (Thomas Eberhard)
Subject: Re 9710 enclosure
Date: Sun, 24 Aug 1997 12:59:41 +0200
Source: Sound Digest Archive v01.n001
>Any information or details on the '70s DIY speaker design?
The Philips 9710 was placed in a bassreflex enclosure with the driver
facing upwards. Peerless cone tweeter are placed in each upper corner. The
9710 have a glassfiber "basket" behind to get a overdamped bass to make it
suitable for placement close to a wall.
This omnidirectional loudspeaker was constructed by the late Stig Carlsson,
there was also a version using the 800 Ohm version of the 9710 and direct
driven by a valve amp. These 800 Ohms driver was Philips reply to the
arrival of transistor amplifers.
Thomas H Eberhard
Klinisk Mikrobiologi VOX 08-5177 49 72
Karolinska Sjukhuset FAX 08-5177 58 50
S 171 76 Stockholm E-M thomas@labmed.ki.se
The great tragedy of Science - the slaying of a beautiful hypothesis
by an ugly fact. - Thomas Henry Huxley
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From: darmah@goodnet.com
Subject: 98 cent mod
Date: Thu, 19 Mar 1998 21:41:43 +0000
Source: Sound Digest Archive v01.n222
Hi Joeneters:
I saw the posts with regard to the 98 cent mod that's on my web page
and wanted to make a quick comment.
The foam I used is very light and has a very open cell structure i.e.
lots of air in it. This may not be the best words but I can't think
of any better way to descreibe it.
I just held a large piece of this stuff up to the monitor and
although I can't read what I'm typing through it I can pretty much
tell what's on the monitor, icons and so on. I think you get the
picture.
Most other types of foam are too heavy and also too stiff. I know
some people who tried things like packaging foam because it's all
they had and this doesn't work too well.
Again, I got mine at the local fabric store.
The strips I cut for drivers wiegh less than 8 % of the total mass of
wizzer and main cone less voice coil assembly.
It doesen't take much to hear the effect. If your going to try this
mod try and get the real light 1/4 inch foam.
Best Regards
Marc S. Wauters
darmah@goodnet.com
Internet Paging: "http://wwp.mirabilis.com/544722"
My Home Page: "http://www.goodnet.com/~darmah/"
Tim Reese