HDTenEightyP/NetNews huggingface dataset:
From: duff@phenom.physics.wisc.edu (Adam Duff)
Newsgroups: rec.audio.high-end
Subject: Modern vacuum tubes for amplifiers?
Date: Fri, 22 Jan 93 17:22:23 -0600
Organization: University of Wisconsin - Milwaukee
NNTP-Posting-Host: 129.89.7.4
Cc: duff@phenom.physics.wisc.edu
Originator: tjk@csd4.csd.uwm.edu


Finally, after many years of use, the tubes in my amplifiers rather
spectacularly bit the dust.  I am now realize that I'm in a more
precarious position than I expected.

First I sent off for one matched pair of KT88's.  Of course, these
are of Chinese manufacture (apparently no one else makes 88's these
days).  They lasted about 3 hours.  Initially they had a rather high
grid current (gassy tube), but one eventually flashed over.  The next
day most of the getter had turned white - a very gassy tube.

I ordered another pair from another supplier (in California).  To make
a short story shorter, they lasted longer than the first, but eventually
died the same spectacular death.

For years I've listened to others complain about the state of modern
vacuum tubes, but now their points really hit home.

I am left in a position that I don't really have a easy solution to.
I am considering the following:

1)  Substitution of New-Old Stock 6550's.  They bias slightly differently,
and I don't have a clue where I could buy a matched pair.
2)  KT90's?  They're supposed to be a more refined tube than the 88's.
I may have to do some circuit tweaking (don't know yet).
3)  KT99's?  This is quite a different tube than the 88's or 90's.  Made
by Tesla in the Czech Republic, it definitely will require some circuit
modifications.  Sonic Frontiers uses them in their amps, and apparently
they like them a great deal.  I don't know anyone other than Sonic Frontiers
who supply them - and they want an arm and a leg for a matched pair.
4)  EL34's?  This would require a more radical circuit modification,
but in principle this would be possible.  EL34's apparently never went
through the same decline as KT88's, since they're in such widespread use
among musicians (ie., Marshall amps).  This has been a much bigger market
than the audiophile market, and will very likely continue to be so.  This
option has the best *long* term prospects (from what I can see).
4)  Go back and get another pair of Sino KT88's.  I really don't want
to do this.

Does anyone out there have any comments or suggestions?  Any help
would be greatly appreciated.

Adam  <duff@phenom.physics.wisc.edu>
From: bhmd1464@altair.selu.edu
Newsgroups: rec.audio.high-end
Subject: Re: Jesus Christ Superstar 20th
Date: 27 Jan 93 19:44:40 -0600
Organization: Southeastern Louisiana University
NNTP-Posting-Host: 129.89.7.4
News-Moderator: Approval required for posting to rec.audio.high-end
Originator: tjk@csd4.csd.uwm.edu

In article <1k63msINN4gj@uwm.edu>, Hallick_Lab@tikal.biosci.arizona.edu (Hallick Lab) writes:
> 
>                        Subject:                               Time:10:52 AM
>   OFFICE MEMO          Jesus Christ Superstar 20th Aniv.      Date:1/26/93
> Has anyone heard the new 20th aniversary recording of J C Superstar done at
> Abby Road Studio?  Any opinions on it relative to the original which just
> became available on CD around here?
> Mitch


I have an Andrew Miller collection CD which includes a few tracks from 
JCS.  I think the quality of these recordings on my disk is absolutely
pathetic.  I hope the 20th anniv. CD you mentioned is better than mine.

Brian Acosta
From: ken@isgtec.com (Ken Newman)
Newsgroups: rec.audio.high-end
Subject: Re: Two great mysteries of audio
Date: Wed, 27 Jan 1993 14:30:48 -0500
Organization: ISG Technologies Inc., Mississauga Ontario
	id <m0nHITM-0000feC@isgtec.isgtec.com>; Wed, 27 Jan 93 19:30 GMT
NNTP-Posting-Host: 129.89.7.4
Originator: tjk@csd4.csd.uwm.edu


In article <1jusfmINNl6l@uwm.edu> gmw1@cunixa.cc.columbia.edu (Gabe M Wiener) writes:
> >1) Why are there no pre-recorded metal cassettes, or no pre-recorded
> >   Dolby C cassettes?
> Probably because:
> 	a) Most people buying cassettes don't care about audio quality.

"Most people" buying CDs don't care about audio quality. What's your point?
"Most people" don't know what audio quality is. :) I didn't advocate
replacing all cassettes with metal ones - just noting that AFAIK there
are *no* pre-recorded metal tapes anywhere.

> 	c) More players have Dolby B than Dolby C

Is this true? Not counting Walkmans for example.

> 	d) Where would you put the "label" ??

Couldn't a very small label be put around the center hole sort of like
LP's? Some CD's go a little nuts on the label issue, with the whole 
cover art etc. You make some good points however.

--

ken@isgtec.com   [ ...!uunet.ca!isgtec!ken ]  Ken Newman
From: lesterw@microsoft.com (Lester Waters)
Newsgroups: rec.audio.high-end
Subject: Re: Comments on Thiel CS2's?
Date: 27 Jan 93 20:29:41 GMT
Organization: Microsoft Corp.
Distribution: usa
NNTP-Posting-Host: 129.89.7.4
Originator: tjk@csd4.csd.uwm.edu

I have a pair of Thiel CS3.6s and they are nothing short
of FANTASTIC.  Very accurate and not thin.  I have
listened to the CS2s (the newer ones) and found them
to be significantly better than anything in the same
price range. Go listen to the CS2s -- you won't be
disappointed!

Thiel also stands behind their products like I've never
seen any other company.  I had a midrange driver problem
and they sent me a replacement THE NEXT DAY - no questions
asked. 

Alsmost the only time I've ever seen used Thiels for sale
is when that person is moving up to another pair of Thiels.
Good luck!
From: gt0179a@prism.gatech.edu (Mike Chu)
Newsgroups: rec.audio.high-end
Subject: Re: RE: Mail Order
Date: 22 Jan 93 17:24:15 GMT
Organization: Georgia Institute of Technology
NNTP-Posting-Host: 129.89.7.4
Originator: tjk@csd4.csd.uwm.edu


in article <1jmi7nINNi48@uwm.edu>, PICHULOR@v9.hanscom.af.mil (Raymond P. Pichulo) says:
> Approved: tjk@csd4.csd.uwm.edu
> NNTP-Posting-Host: 129.89.7.4
> Originator: tjk@csd4.csd.uwm.edu
> 
>>I agree 100%!  Besides what could be more unethical than retail
>>capitalism in the first place!!  Anyway, I think it is very important to
>>give your local dealer a chance to match prices with mailorder.  As Gary
>>points out, mail order dealers are still making a profit and many times
>>your local dealer will come close (or even beat) the mail order price --
>>especially when you consider how much you will spend on shipping..
> 
> Don't compare apples and oranges.  The mail order dealer doesn't have the
> overhead of maintaining demos, loaners, a showroom, etc. that your retail
> dealer has, so you can't honestly expect him to match the mail order price.
> You've got to give the retail dealer some allowance for this

Isn't this rec.audio.high-end?  Well if it is I doubt many (if any at all)
mail order stores even exist for high-end components without a showroom, etc...
I've personally bought products from Sqaure Deal, Savant A&V, Stereo Exchange,
and Audio Connection... all of which have huge product lines, demos, etc...
Of course they are able to order in larger volumes than local stores,
but frankly, I'm not Donald Trump and, I have to "wheel and deal" to
get the most for my money.  And, another reason for mail ordering is
the lack of quality retail stores in my area (the deep south).  The folks
down here seem to carry only product lines that have mass appeal to 
the typical "magazine reading" audiophile... you know: Acurus, Vandersteen,
Snell, PSB, blah, blah, blah.  If I want to get the best products for
competative prices I must resort to mail order.  Furthermore, competition
is a vital aspect of retailing... without it pricces would be sky high!

Mike
.
-- 
Mike Chu  --  Chemical Engineering
Georgia Institute of Technology, Atlanta Georgia, 30332
uucp:	  ...!{decvax,hplabs,ncar,purdue,rutgers}!gatech!prism!gt0179a
Internet: gt0179a@prism.gatech.edu
From: youngd@Panix.Com (David Young)
Newsgroups: rec.audio.high-end
Subject: Sony SBM, HDCD and dunhill Compact
Date: Thu, 21 Jan 1993 14:25:53 GMT
Organization: PANIX Public Access Unix, NYC
  (5.65c/IDA-1.4.4 for uunet!rec-audio-high-end); Thu, 21 Jan 1993 09:25:56 -0500
NNTP-Posting-Host: 129.89.7.4
Summary: difference bet new CD recording
Keywords: CD
Originator: tjk@csd4.csd.uwm.edu


	any one heard all three differenct CDs? the sony super bit mapping
	the HDCD and a regular CD press by Dunhill Compact Disk.

	I heard different story about the sound quality of the HDCD,
	sony's SBM CD, and this dunhill compact disk that's suppose
	to make a very good recording out of old Master Tape.

dy
From: kchau@sfu.ca (Kwok Kwong Albert Chau)
Newsgroups: rec.audio.high-end
Subject: HDCD Patents
Date: Thu, 21 Jan 1993 03:48:47 GMT
Organization: Simon Fraser University, Burnaby, B.C., Canada
Distribution: na
NNTP-Posting-Host: 129.89.7.4
Keywords: HDCD
Originator: tjk@csd4.csd.uwm.edu

This seems too simple, but aren't pending patents available for public
scrutiny as are patents granted.  I'm probably wwrong on this but I
seem to remember being told that this is so.  If this is the case the
question of how HDCD works is easily answered/dug up.

Albert Chau
kchau@sfu.ca
From: qazi@csd4.csd.uwm.edu (Aamir Hafeez Qazi)
Newsgroups: rec.audio.high-end
Subject: Moving coil headamp
Date: 20 Jan 1993 21:37:29 GMT
Organization: Computing Services Division, University of Wisconsin - Milwaukee
Distribution: usa
NNTP-Posting-Host: 129.89.7.4
Originator: qazi@csd4.csd.uwm.edu
Originator: tjk@csd4.csd.uwm.edu


My dad has a Powerlight Studio MC-5 Moving Coil Headamp (or pre-preamp)
for use with a moving coil cartridge.  He doesn't need it anymore, so I
thought I'd ask if anyone is interested in purchasing it.  I am wondering
if such units are being used anymore, since I don't know anything about
turntables/cartridges and the like.  It is a small unit (6.5" x 4.5" x
1.75"), and it works just fine, from what I am told.  Please e-mail me
if you or anyone you know are interested, or if you want more information
about the unit.

Thanks,

Aamir Qazi

-- 

Aamir Qazi
qazi@csd4.csd.uwm.edu
--Why should I care?  I'd rather watch drying paint.
From: matthews@eecs.ucdavis.edu (Thomas W. Matthews)
Newsgroups: rec.audio.high-end
Subject: Re: Digital Amps.. Possible?
Date: 28 Jan 93 00:17:53 GMT
Organization: Division of Electrical Engineering and Computer Science, UC Davis
NNTP-Posting-Host: 129.89.7.4
Originator: tjk@csd4.csd.uwm.edu


In  <1jusg9INNl7d@uwm.edu>   chrz@tellabs.com (Peter Chrzanowski) writes:

>Sony actually marketed a pulse-width-modulated amplifier in the U.S.A. in
>the late '70s (model TA1000?).  The idea wasn't original with Sony, however,
>and has been around for a long time.
>
>The width of the high frequency pulses (the Sony's basic pulse freq.
>was about 100Khz) is narrow for low-amplitude analog inputs, wide
>for large inputs.  The original waveform can then be recovered by
>integrating the pulses, which can be done with reasonable accuracy
>using a series inductor followed by a bypass capacitor (choke input
>lowpass filter).

It seems like the pulse width could be determined _directly_ from 
the digital data, if one wanted to use a digital interconnect to the
power amplifier.  This would be analogous to a one-bit D/A done
with high power switches directly across the speaker as a load.

It's not without its problems, but it is a new(?) approach . . .

Tom Matthews
From: apctrc!znpt01@uunet.UU.NET (Norman P. Tracy)
Newsgroups: rec.audio.high-end
Subject: Re: Repairing the AR ES1 turntable
Date: Mon, 25 Jan 1993 18:38:42 GMT
Organization: Amoco Production Company, Tulsa Research
	(queueing-rmail) id 141951.24632; Mon, 25 Jan 1993 14:19:51 EST
NNTP-Posting-Host: 129.89.7.4
Originator: znpt01@gpss43
Originator: tjk@csd4.csd.uwm.edu


A good source for users, repairers, and modifiers of AR
turntables is:

Merrill Audio  (a.k.a. Underground Sound)
2125 Central Ave.
Memphis TN 38104  ph. # 901-272-1275

Merrill is the maker of the Merrill turntable and a
tt kit.  These both evolved out of their many years
of upgradeing AR tts.  I've helped set up a Merrill
and it was a very high quality unit, most impresive.

Norman Tracy
-- 
Norman Tracy

znpt01@trc.amoco.com
From: Craig Stark <cs6h+@andrew.cmu.edu>
Newsgroups: rec.audio.high-end
Subject: Re: Where to buy speaker drivers
Date: Tue, 26 Jan 1993 15:56:56 -0500 (EST)
Organization: University of Wisconsin - Milwaukee
NNTP-Posting-Host: 129.89.7.4
Originator: tjk@csd4.csd.uwm.edu

I've done a lot of business with Madisound in Madison, WI.  They're
fast, friendly, reasonably priced and quite knowledgeable.
Furthermore, they carry better drivers than MCM or Parts Express
(Dynaudio, Focal, Audax, Peerless, Eton, Morel and many others) and
offer a good selection of coils, caps, etc.  Unfortunately, I don't
have their phone number on me here in the office, but I know
information has it.

Craig Stark
From: Craig Stark <cs6h+@andrew.cmu.edu>
        ctlant@lims01.lerc.nasa.gov (CHRISTIAN LANT)
Newsgroups: rec.audio.high-end
Subject: Re: Need a replacement Polk tweeter
Date: Sun, 24 Jan 1993 15:01:32 -0500 (EST)
Organization: University of Wisconsin - Milwaukee
NNTP-Posting-Host: 129.89.7.4
Originator: tjk@csd4.csd.uwm.edu

Can you describe the tweeter physically?  One of Polk's stock tweeters
looks a heck of a lot like a common Peerless tweeter that is used in a
number of commercial designs.  What shape is the flange?  Are there
two diagonal grooves running down and out from the dome?

Craig Stark
From: zaphod@ctrg.rri.uwo.ca (Lance R. Bailey)
Newsgroups: rec.audio.high-end
Subject: Re: Oracle Alexandria Belt
Date: Mon, 25 Jan 1993 12:11:12 GMT
Organization: University of Western Ontario
Distribution: rec
Reply-To: zaphod@ctrg.rri.uwo.ca
NNTP-Posting-Host: 129.89.7.4
Originator: tjk@csd4.csd.uwm.edu

In article <1jusfkINNl6j@uwm.edu> ezad133@hermes.chpc.utexas.edu (Jim A.  
Andrews) writes:

>Does anyone know where I can get a replacement belt for my
>Oracle Alexandria (II?) table?  My local audio shops have
>been unable to help.  I think Oracle has had numerous 
>problems in the past -- are they still in business?  Thanks . . .

they are still in business, contact them at:

Oracle
PO.Box  394
Edmunston,New Brunswick
E3C 3L1, Canada
1-506-735-1080


--
Lance R. Bailey  System/Network Manager         Robarts Research Institute
     NeXT/email: zaphod@ctrg.rri.uwo.ca    box: Clinical Trials Resources Group
            fax: +1 519 663 3789                P.O. Box 5015, 100 Perth Dr.
            vox: +1 519 663 3787 x4108          London, Canada N6A 5K8
186,000 mps: It's not only a good idea, it's the law. -- Frank Wu
From: yschin@ccu.umanitoba.ca (Yu-Shin Chin)
Newsgroups: rec.audio.high-end
Subject: Re: Decent EQs?
Date: Wed, 27 Jan 1993 23:09:39 GMT
Organization: University of Manitoba, Canada
	id <AA00033>; Wed, 27 Jan 93 18:10:45 -0500
NNTP-Posting-Host: 129.89.7.4
Originator: tjk@csd4.csd.uwm.edu

In article <1k3fsbINNkjt@uwm.edu>, schiesel-seth@YALE.EDU (Seth Schiesel) writes:
|> First, the flame-guard. I *know* a real audiophile doesn't use an EQ but I
|> listen to many, many "bootleg" recordings of live concerts (don't flame me
|> on that either, please, because the band I listen to allows it), and would
|> like to do whatever I can to make them sound better. So... I would
|> appreciate any recommendations on an equalizer that doesn't ruin the music
|> under $1000. Thanks,

Real audiophiles do use EQ's since most rooms are not acoustically
perfect or even near perfect.  A good EQ allows you to "flatten" your
room as much as possible.  Although a flat response may not be what you
like, you can adjust the EQ in any way you like.  I think the EQ
enhances the sound quality of any type of music since you have much
more control in your bass, treble, and midrange as compared to just the
controls on your amplifier or receiver. I haven't kept up with the
current line of EQ's in past t wo or three years but a good brand to
look at is the higher end of the AUDIO CONTROL line.
From: mlloyd@ihlpm.att.com
Newsgroups: rec.audio.high-end
Subject: sources of hafler amps, IGBTs, big heatsinks?
Date: Wed, 20 Jan 93 17:11 CST
Organization: University of Wisconsin - Milwaukee
NNTP-Posting-Host: 129.89.7.4
Original-From: ihlpm!mlloyd (Michael Lloyd +1 708 713 5497)
Originator: tjk@csd4.csd.uwm.edu


Greetings:

A few questions:

1. Can anyone recommend a decent mailorder source for hafler stuff?
   I'm looking for one of the smaller amps (for background listening 
   in a small room): the 9100 or 9300, not the trans-nova products. 
   My local dealers insist on selling for full MSRP, so I walked!

2. Does anyone know where I can get some (maybe 10 pairs or so) of
   these Toshiba transistors (IGBT): GT20D201 and GT20D101. I'm not
   having much luck with the local dealers. Maybe there's enough
   people looking to suggest a group purchase?

3. For you folks making class-A or high-powered amps, what do you do
   for heatsinks? Is the only way to get "Threshhold like" heatsinks
   to buy a Threshhold amp and gut it :-) ?

And one suggestion: for folks looking for a great homebrew linestage
(and are not afraid to tell your friends you can listen to op amps :-) )
the AD744 (sans out stage) driving the AD811 as suggested in a recent 
"The Audio Amateur" and the Analog Devices Design Seminar handbook) is 
hard to beat! 

Michael Lloyd
From: "Andreas G. Yankopolus" <ay0i+@andrew.cmu.edu>
Newsgroups: rec.audio.high-end
Subject: Re: Comments on Thiel CS2's?
Date: Tue, 26 Jan 1993 13:09:50 -0500 (EST)
Organization: University of Wisconsin - Milwaukee
NNTP-Posting-Host: 129.89.7.4
Cc: 
Originator: tjk@csd4.csd.uwm.edu

While the CS 2s are great speakers, I actually prefer the CS 1.2s (which
I also happen to own).  The CS 2s have deeper bass extension, but that's
about it.  In the midrange and treble, the CS1.2s sound much smoother
and more transparent to my ear.  Then again, I generally like two-way
designs (the larger Thiels and WATT/Puppies are notable exceptions). 
I'm sure a lot of the difference is covered by CS1.2 being a newer
design.

As far as reliablility goes, I have abused my CS1.2s quite a bit and
only had them give out on me once (the voice coil tore off the bass
driver).  I had a new driver within four days under Thiel's 10 year
warranty.  Thiel has also been business since 1983 (please correct me if
I'm wrong here)


Andreas Yankopolus
Carnegie-Mellon University
Junior, Electrical Engineering
From: mlloyd@ihlpm.att.com
Newsgroups: rec.audio.high-end
Subject: address for APT parts?
Date: Mon, 25 Jan 93 12:03 CST
Organization: University of Wisconsin - Milwaukee
NNTP-Posting-Host: 129.89.7.4
Original-From: ihlpm!mlloyd (Michael Lloyd +1 708 713 5497)
Originator: tjk@csd4.csd.uwm.edu

Greetings:

I have an APT 1 power amp that was destroyed by lightning. Most semi-
conductors were damaged/degraded and the main PCBs were scorched. As 
an ongoing project, I would like to restore the amp. Can anyone suggest 
an address or someone to contact for replacement parts? Actually, what 
I'll need are unstuffed circuit cards for the gain stages; the protection
and indicator boards were not as badly damaged. I have/can get the parts 
to repopulate the boards.

Thanx!
Michael Lloyd
From: jas@proteon.com (John A. Shriver)
Newsgroups: rec.audio.high-end
Subject: Glass Audio subscription information
Date: Wed, 27 Jan 93 10:28:40 EST
Organization: University of Wisconsin - Milwaukee
NNTP-Posting-Host: 129.89.7.4
Originator: tjk@csd4.csd.uwm.edu

Given that there were so many requests, here's subscription
information on Glass Audio.

US: USD 20 per year
Canada: USD 24 per year
Overseas: USD 30 per year

Glass Audio
PO BOx 176
Peterborough, NH  03458-0176
USA

Phone: +1 603 924-9464
FAX:   +1 603 924-9467

There are four issues a year.  Proofreading and copy editing are less
than perfect, I'd never build anything until the next issue arrived
with corrections.  One recent article on a regulated power supply was
so ridden with errors they just completely reprinted it the next
issue.  Also, some of the schematics are so poorly laid out as to be
incomprehensible, I had to redraw the recent OTL power amp to be able
to understand the article.

(It looks like they stopped paying Ken Kesseler for his column
starting with this first 1993 issue, good riddance.)

They also publish Audio Amateur (mostly solid state designs since
Glass Audio started 5 years ago) and Speaker Builder.

The electronic design articles in all three are generally of high end
sensibilities.  Plenty of notables have written articles (particularly
for Audio Amateur), including Walt Jung (of Analog Devices), Nelson
Pass (of Threshold and now Pass Labs), Erno Borberly (ex of Dynaco),
and Gary Galo.  Reg Williamson (good deisgner, but adamantly
anti-high-end) also writes for them.

To some degree, all of the magazines are feeders for their Old Colony
Sound Labs, who sell PC boards and parts kits for most articles.  The
PC boards are fairly priced and good quality, the kits are more
overpriced.

Realize that these are not refereed journals, there is no guarantee
that any design is competent or stable.  Note the credentials of the
authors before proceeding.

All of them have ads for good sources of parts.
From: bhmd1464@altair.selu.edu
Newsgroups: rec.audio.high-end
Subject: Wanted:Infinity Speakers
Date: 21 Jan 93 14:52:48 -0600
Organization: Southeastern Louisiana University
NNTP-Posting-Host: 129.89.7.4
News-Moderator: Approval required for posting to rec.audio.high-end
Originator: tjk@csd4.csd.uwm.edu

I am looking for a pair of Infinity Kappa-9 speakers
AND a pair of Kappa-8.  Anyone with any information
that would help me find these, please e-mail me.

Thanks,

Brian Acosta
From: acgd@ihlpl.att.com
Newsgroups: rec.audio.high-end
Subject: EAD DSP 7000 Upgrade
Date: Mon, 25 Jan 93 18:24:13 EST
Organization: AT&T
NNTP-Posting-Host: 129.89.7.4
Keywords: Has anyone heard it?
Originator: tjk@csd4.csd.uwm.edu

Has anyone auditioned either of the following? (Especially as compared to
the "regular" DSP 7000):

	- EAD DSP 9000
	- EAD DSP 7000 Series II

I have a DSP 7000 (original w/receiver chip upgrade) and am curious about
the value of their upgrade package (which would make it a "series II").

I know what's in the package and how much it costs...does anyone have any
comments on how it sounds?

Andrew Charles
acgd@ihlpl.att.com

p.s. I'll be checking w/my dealer too to see if I can home audition the
series II sometime but I'm still curious about what others think.