HDTenEightyP/NetNews huggingface dataset:
From: rkarlqu@scd.hp.com (Richard Karlquist)
Newsgroups: rec.audio
Subject: Re: Question on choke-input filters.
Date: 9 Nov 1992 07:06:37 GMT
Organization: Hewlett Packard Santa Clara Division
NNTP-Posting-Host: hpscrj.scd.hp.com
X-Newsreader: TIN [version 1.1.4 PL6]

Henry Pasternack (henry@monod.Biol.McGill.CA) wrote:
:    I'd like to know more about practical choke-input filters
: for vacuum tube power amplifiers.  My biggest concern has to
: do with filter bounce.  Specifically, is there a tendency for
: a filter with a large LC product to generate resonant voltage
: spikes when the envelope frequency of the musical waveform is
: close to the filter resonant frequency?

If the resonant frequency of the input choke and filter capacitor
(= 1/2*pi*L*C) gets anywhere near as high as the AC frequency
(60 Hz.), you're in serious trouble anyway.  If you have any
design margin at all, this resonance will be way below 20 Hz.
so it won't affect audio.

: 
:    I have a couple of reasons for wanting to use a choke-input
: filter.  Primarily, I have some transformers with 1000VCT
: secondaries and a capacitor-input filter gives me too much B+
: voltage (around 700VDC), while a choke-input filter produces
: a more reasonable 450V.  The second reason is that choke-input
: filters have superior regulation.

Yes, but only above the critical current.  This requires you to
put a bleeder resistor on the output, unless your amplifier runs
class A.  The bleeder power is quite large unless you use a
"swinging choke", which is virtually impossible to obtain these
days.  If you put a big bleeder resistor on a capacitor input
filter, it will also improve the regulation.

: 
:    If you have bona-fide experience with choke-input filters
: in this type of application, I'd like to hear from you.  Thanks.

This is a dim-bulb idea.  It is far easier to get another 
power transformer than to find a suitable choke.  The only 
reason choke input filters were ever used in the first place
was because they don't require high peak currents in the 
rectifiers, and this was a problem for high vacuum rectifier
tubes.  Even vacuum tube buffs like you now use solid state
rectifiers, I would hope.  Solid state rectifiers can easily
handle high peak currents.

: 
: -Henry

--
       -------------------------------------------------
       |  Rick Karlquist                               |
       |  Hewlett-Packard Santa Clara Division         |
       |  Precision Time and Frequency R&D             |
       |                                               |
       |  email:  rkarlqu@scd.hp.com                   |
       |  landline:  (408)-553-2194                    |
       |  radio:  N6RK                                 |
       ------------------------------------------------
From: lstowell@pyrnova.mis.pyramid.com (Lon Stowell)
Newsgroups: rec.audio
Subject: Re: To the guy who flamed Infinity
Date: 12 Nov 92 19:01:24 GMT
Reply-To: lstowell@pyrnova.pyramid.com (Lon Stowell)
Organization: Pyramid Technology Corp., Mountain View, CA

In article <1992Nov12.003310.65290@ns1.cc.lehigh.edu> ptb2@ns1.cc.lehigh.edu (PETER TALAN BERGEN) writes:
>>--
>Not all of us have $2500 or more to spend on a set of speakers, some of us are
>paying 23 G's for a college education.  GET A CLUE!!!!!!!!!


    So ignore the articles that talk about them!   Not all of us are
    penniless college students either.

    If you're so !@#$ broke and busy, how come you even read the
    board in the first place?  

    Oh, and you might want to sign up for "Remedial Clue 101"
    yourself.  This stinkin board was here before you figured out
    how to type and it will be here after you are flunked out or
    graduated...and it isn't likely to change to meet your personal
    prejudices--unless you become God sometime soon.
From: shli@pollux.usc.edu (Shih-Hao Li)
Newsgroups: rec.audio
Subject: Forte Preamp
Date: 6 Nov 1992 09:35:30 -0800
Organization: University of Southern California, Los Angeles, CA
Distribution: usa
NNTP-Posting-Host: pollux.usc.edu


Does anyone have experiences on Forte PreAmp?
How does it compare to Adcom?

Thanks in advance!!
SH
Newsgroups: rec.audio
From: jim@fuji.eng.yale.edu (James J. Szinger)
Subject: Re: Wire to Center Channel
Organization: Yale University, Intelligent Sensors Lab, Elect. Eng.
	<PHILG.92Nov11172455@zug.ai.mit.edu> <1ds8u8INNd2e@agate.berkeley.edu>
	<1992Nov12.140308.1639@bilver.uucp>
Date: Thu, 12 Nov 1992 15:10:19 GMT

In article <1992Nov12.140308.1639@bilver.uucp> bill@bilver.uucp
(Bill Vermillion) writes:

>Let's take another example. If you were REALLY sloppy in your
>measurements and you mis-cut the wire and had one longer
>than the other by some amount - for example - of 1000 feet.  You would
>be getting phase shift on the frequencies in the 1MHz range.

This is almost as bad as putting a dispersive medium between the
sound source and the listener.  Let's imagine that the speed of
sound depend on the frequency so c(20Hz)=1128.386ft/sec and
c(20kHz)=1128.549ft/sec.  Now let us imagine that the sound had
to travel 100 feet through this medium before it gets to the
listener.  This works out to a delay of 0.0128ms between the low
and high frequencies.  This can also be viewed as the 20kHz tone
being phase shifted by 92 degrees with respect to the 20Hz tone!

In case you're thinking to yourself that you're glad that you don't
have to listen to anything that bad, you're probably wrong.  The
numbers are for air with a temperature of 20C (68F) and a
relative humidity of 50%.  

Jim
--
James Szinger                        jim@fuji.eng.yale.edu

"He was born with a gift of laughter and a sense that the world was mad."
From: pcw@flutter.tv.tek.com (Patrick C. Wilkins)
Newsgroups: rec.audio
Subject: Re: Difference between Sony TAE-1000ES and TAE-2000ES
Date: 14 Nov 92 02:19:13 GMT
Article-I.D.: flutter.PCW.92Nov13181913
Organization: Tektronix TV Products

Robert, I just posted the following article a couple of days ago.
I'm seriously considering buying a DSP-A1000 and would like opinions.

Hello netlanders,
has anyone evaluated the Yamaha DSP-A1000 with respect to surround decoding
while adding acoustic compensation via the DSP. I recently listened to 
a demonstration comparing the Yamaha RX-V1050 5-channel Pro-logic receiver
and the DSP-A1000 7-channel with acoustic compensation (DSP) at a finer 
stereo store. The source material was a short section of movie track which 
contained, dialog, orchestra, and various effects. The difference between 
the material through just the Pro-logic decoding (RX-V1050) and Pro-logic 
with DSP (DSP-A1000) was dramatic. The DSP-A1000 had a much larger sound-
stage yet the dialog was very well centered and easier to localize that
with the RX-V1050. Unless the demostration is a carefully contrived
promotion for the DSP-A1000, I think the DSP-A1000 is well worth the 
additional money just for movie tracks. Comments about or personal 
experience with these products?
Thanks,

--

-------------------------------------------------------------------
    Pat Wilkins II
    A.K.A. Clif
    Email pcw@flutter.tv.tek.com
    Work 503-627-6525

-------------------------------------------------------------------
    Is Deja-vu real or is life just redundant???????
-------------------------------------------------------------------
From: mike@banana.fedex.com (Mike Bearden)
Newsgroups: rec.audio
Subject: NAD FOR SALE - Preamp/Tuner
Date: 11 Nov 92 18:33:17 GMT
Distribution: rec
Organization: Federal Express Corp.











     For Sale:  NAD 1155 Preamp

                NAD 4020A Tuner

                Both mint.

                $250 gets both units, shipping included.


      Mike Bearden
      (901)797-6350  Work/Days
      (901)756-8517  HOme/Nights
Newsgroups: rec.audio
Subject: Re: Dennon vs. Sony
From: oberland@vax.sonoma.edu
Date: 12 Nov 92 01:32:36 -0800
Organization: Sonoma State University

Um...
Well, It won't burn paper, but you'd be amazed at what gets
krispy at a little less.(300-ish range)
This Amp is a 100WPC 20 yr-old beast, and weighs about 50lbs, about
40lbs being the "guts".  They don't make them like this anymore, and I
think I know why...(heh)
"...and I can sell you the cooling option right here for 200 more..."
:)

I am in the same situation as most everyone else around here, and in
many semi-rural areas.  Marginal power.  Worse wiring and breakers.
Turn that Microwave or AC on and watch the fun.(joke :) )
(It almost is that bad, tho...)

My point was that I am not alone in having poor conditions, and I have
learned to err on the side of over-built equipment.  I like my dennon because
it is built a bit better(enough for my needs)than the Sony.
It is about the only thing that HAS lasted more than 2 years without
any problems, come to think of it.Nothing seems to last, anymore...

Of course, my machine is not nearly as good as what is now being made.
My friend's top-of-the-line NAD(about 3 yrs older than mine) is proof of that.
Mine beats his, just like the new computers do over 1 yr-old technology.

Also, loosing 2 small devices(boombox and a modem) to power surges over
4-5 years is not too bad, IMO.  My power is fairly decent, except in summer,
when the local utility likes to play the late-night switching game.
Shoot.. they do it pretty regularly as of late...

Now if they could just fix the phone lines...
Error correction only works MOST of the time, it is so bad.
(ag!)

Joe
Come to think of it, I may have something wrong with the Amp.  Goinna check
the heat-sink tomorrow...probably is fried with my luck...
From: rmihara@ocf.berkeley.edu (Randall A. Mihara)
Newsgroups: rec.audio
Subject: Re: DCC, MD Limitations
Date: 11 Nov 1992 17:39:51 GMT
Organization: U.C. Berkeley Open Computing Facility
NNTP-Posting-Host: earthquake.berkeley.edu

In article <of07=ae00WAuMm90Qm@andrew.cmu.edu> Brian T Cheek <bc2y+@andrew.cmu.edu> writes:
>What would happen if you recorded a whisper + loud electric guitar sound
>on either MD or DCC.  The whisper would be dropped, correct?

not necessarily.  the data compression using psychoacoustical masking
effect goes beyond mere amplitude masking.  the techniques used are
designed to be selectively lossy.  That is, spectral components that the 
average human ear could not detect anyway are discarded.  The main
gripe should be for people that have better than average hearing...they
may be able to detect the difference between CD and MD.

>How can people tell the difference between real pianos and sampled ones?
>Real piano strings resonate the other ones.  (Hard to hear, but you
>don't want to throw them away, now.

agreed.  There is some degradation is sound quality.  I would personally
prefer to keep all the original sound data in tact.

>Why will MD and DCC take a LONG time to mature?
>1. Record stores can't afford to keep them with the small demand

One of the main reasons MD and DCC have been delayed in their release
is so that pre-recorded media can be produced.  It has been said
that DAT didn't do as well as it should have due to its lack of
media availablity at the time of release.

>2. People can't even program their VCR's yet.
>3. Smart people will wait for true CD quality, (like DAT now, which

observations 2 and 3...answer themselves.  MD and DCC are not marketing
for the audiophiles.  They are targetting the average consumer, who,
as you say, can't even program their VCR (or VCR Plus).  The vast majority
of average buttheads...I mean consumers...won't even notice the difference
in quality between md and cd.  What I find puzzling,however, it why
they are selling the units at such a high price.  They originally planned
to sell them for a low price with the intent that the average person can
buy them.  Their prices seem to undermine their market.  If you
are an audiophile, you will probably want to wait a while for the
recordable CD.

Randy Mihara
rmihara@ocf.berkeley.edu
Newsgroups: rec.audio
From: nau@ssesco.com (William Nau)
Subject: Re: How 'bout a new group for the rest of us?
Organization: SSESCO
Date: Fri, 13 Nov 1992 13:33:09 GMT

Come on.  How about we all get along in this news group.  Bob can have
his $20,000 system and Jim can have his $200 system.  I'll have one
inbetween.  You know ya can often learn a lot about buying your system
from someone who has a better one.  They've been though it and can have
some good advice.  Sure you run into snobs.  Where don't you?  Most
of the readers of this group (even those with $20,000 systems) understand
that we all have budgets.  Make it clear that you have a $250 budget
for that CD player and people won't suggest $5000 CD players to you.

It's very nice to have access to all of these people with their varied
knowledge and experience.  I really don't want to isolate it.

-- 
William R. Nau
Supercomputer Systems Engineering and Services Company (SSESCO)
511 11th Avenue South, Suite 216
Minneapolis, Minnesota 55415-1536
(612) 342-0003

nau@SSESCO.com
From: sh09@ns1.cc.lehigh.edu (STEVEN HIGGINS)
Newsgroups: rec.audio
Subject: Re: Rack mounting components
Date: 11 Nov 92 20:02:07 GMT
Organization: Lehigh University

In article <BxJ74H.HtB@ns1.nodak.edu>, mcelmury@plains.NoDak.edu (Michael McElmu
ry) writes:
>I have built up quite a bit of stereo components and decided that
>I would like to rack mount everything. I found a rack that is about
>what I want, however, the rack would require some of the components
>(all but my two amps) to be placed at about a 35 - 40 degree angle
>from verticle. My question, how would my CD player (Adcom GCD 575)
>react to this placement in the long run? I tried tilting the player
>as it was playing a disk and it didn't seem to affect it. Would
>extended use in this position hurt anything?
>

    Standard audio racks are 19" on center, which should be _MORE_ than wide
    enough for home audio equipment.  What are you looking at???

    
-- 
--Steve Higgins
  sh09@lehigh.edu
From: dna@ampex.com (David Altekruse)
Newsgroups: rec.audio
Subject: Re: Pro Logic Center ch. and SUBwoofers...
Date: 6 Nov 92 21:48:09 GMT
Article-I.D.: ampex.1992Nov6.214809.4559
Organization: Ampex Corporation, Redwood City CA

In article <24108@alice.att.com> andrew@alice.att.com (Andrew Hume) writes:
>
>
>	before more rumours start and people start accusing hsu
>of rippoff prices, let me point out their prices have dropped.
>I believe when they started they were $500 each (most people seem to
>only want one subwoofer). they are now $750/pair. there seems to
>be growing acceptance that most subwoofers are giving significant
>output at frequencies high enough that you would want a stereo pair.
>
>		andrew
>
Not so.  I have a price list from about two months ago that clearly states
$500 a PAIR for the 10" model and $1000 a PAIR for the 12".

- David Altekruse, dna@ampex.com
Newsgroups: rec.audio
From: dna@ampex.com (David Altekruse)
Subject: Re: Pro Logic Center channel speakers
Keywords: pro logic
Organization: Ampex Corporation, Redwood City CA
Date: Thu, 5 Nov 1992 23:58:31 GMT

Mike Marks writes:
>
>What do you use for a center channel if your mains are Magneplanar
>MG-III's.  At 6' high by 2' wide, I can't just stick one of these
>in the center if I want to see the screen.  A traditional "box"
>center channel isn't going to tonally matched to the maggies.  Should
>I just use the phantom mode?
>
I am interested in this question as well.  I also have MG-III's flanking
a 100" screen.  I have 26" under the screen.  I could get a third MG-III 
speaker and set it on its side.  (I'm kidding.)  My guess is that the
phantom mode is the best way to go for the person sitting in the center
sweet-spot.  After all, I don't even have a Pro-Logic decoder yet and
the dialog sounds dead center to me.  But not to people sitting off to the
side.  Anyway, I'd also be interested in knowing what people with bi/di-polar
L-R speakers use for the center channel.

I have a second related question:  Is anyone using the Yamaha A/E-1000 with
bi/di-polar speakers?  Do the front effect speakers add much in this case?
(Sound is already being reflected back by the main bi/di-polar speakers.)
And what front effect speakers are you using?

- David Altekruse, dna@ampex.com
From: rkarlqu@scd.hp.com (Richard Karlquist)
Newsgroups: rec.audio
Subject: Re: A Timer/Recorder for AM/FM Radio?
Date: 6 Nov 92 14:54:27 GMT
Article-I.D.: hpscdf.1de0v3INNpiq
Organization: Hewlett Packard Santa Clara Division
NNTP-Posting-Host: hpscrj.scd.hp.com
X-Newsreader: TIN [version 1.1.4 PL6]

David Oesper (F1.DAO@isumvs.iastate.edu) wrote:
: Does anyone make an affordable component that allows one to record
: AM and FM radio programs in much the same way any VCR works?  What I
: am looking for would have the following features:
: 
: (1) Be able to record programs up to 2 hours long on a single tape.
: 
: (2) Have a built-in timer where you would program the time,
: frequency (on either AM or FM), and program duration (like a VCR).
: 
: In other words, what I am looking for is a VCR for radio instead of
: for television.  Does such a thing exist?

No, such a thing does NOT exist.  Here are the closest approximations:

     1.  Panasonic makes a clock radio with built-in cassette deck
which can record from the built in radio to the built-in cassette using
the built-in clock.  However, I don't think it is autoreverse, so the
longest recording time you can get is 1 hour on a C-120.

     2.  Almost any decent cassette deck you buy these days has a "timer
switch".  If set to "record", this will put the deck into record when it
is powered up.  Simply plug the deck into an X-10 module (available at
Radio Shack), and use an X-10 timer to power it up when your show comes on.
There have also been tuners made with built in timers for this purpose.

     3.  Buy a cassette deck with IR remote control and use a universal
remote with timer to activate it.  See the recent posting on rec.audio
about this topic.

     4.  Use a VCR for audio only recording.  You may have to supply the
VCR with some sort of a video signal to keep its sync circuits happy. 

       -------------------------------------------------
       |  Rick Karlquist                               |
       |  Hewlett-Packard Santa Clara Division         |
       |  Precision Time and Frequency R&D             |
       |                                               |
       |  email:  rkarlqu@scd.hp.com                   |
       |  landline:  (408)-553-2194                    |
       |  radio:  N6RK                                 |
       ------------------------------------------------
Newsgroups: rec.audio,rec.audio.pro,comp.sys.ibm.pc.soundcard,comp.multimedia
From: cnwietho@immd4.informatik.uni-erlangen.de (Carsten Wiethoff)
Subject: Re: Interface Digital Audio <---> Computer ???
Organization: CSD., University of Erlangen, Germany
Date: Thu, 12 Nov 1992 14:18:28 GMT

From article <BxHFx7.KFp@ux1.cso.uiuc.edu>, by adcg9841@uxa.cso.uiuc.edu (flannelman):
> Hey folks.  Does anybody want to answer the original question with respect
> to the IBM pc?  Some of us have pc's now and are not interested in the
> NeXT or the Indigo.  I, for one, would prefer that this NOT turn into a
> comparison of the different platforms, but instead that someone who knows
> about the latest AES/EBU-type boards for the pc speak up with information.
Let me extend the question to SBus Cards for SUNs. The only solution I
found was the DSP from Ariel together with the interface from DAT to DSP.
The price for this combination is too high for my private budget.  :-(

Carsten Wiethoff (pwi@psun3.hmi.de)

Newsgroups: rec.audio,rec.audio.pro,comp.sys.ibm.pc.soundcard,comp.multimedia
From: gmw1@cunixa.cc.columbia.edu (Gabe M Wiener)
Subject: Re: Interface Digital Audio <---> Computer ???
Reply-To: gmw1@cunixa.cc.columbia.edu (Gabe M Wiener)
Organization: Columbia University
Date: Mon, 9 Nov 1992 16:11:59 GMT

In article <1992Nov9.144423.7532@rhrk.uni-kl.de> luitz@rhrk.uni-kl.de (Steffen Luitz [RHRK]) writes:
>what about an interface digital audio (DAT, CD optical or coax) to 
>a computer system (perhaps SCSI or a PC-board  or ...) ?
>Nooo, I don't want to make my backups with my DAT recorder, but it
>would be very interesting to edit my recordings in some way with 
>the computer and the most obvious way seems to copy data from DAT
>recorder to the computer, do the cutting, filtering ... and copy
>everything back to a DAT tape.

Errr....you're a little late.  Digital Audio Workstations have existed
for years, and are used on nearly all recordings made today.  The idea
is basically as you described.  You load your session tapes onto the machine,
do your editing on the hard drive, and then off-load the final version onto
DAT, CDR, PCM-1630, whatever.  Not a big deal.

The systems range in price from a few thousand dollars (SoundTools) to 
many hundreds of thousands (a full Sonic System).  Some of them are just
plug-in cards for existing computers, usually Macs or PC's, and some have
dedicated CPU's with esoteric designs.

Perhaps the best of the systems is the Sonic Solutions, as it can be
configured for as low as $4,995 (plus the computer) for the basic system,
and can be expanded in stages all the way up to full-blown CD cutting system
with NoNOISE processing (well over $100K).


--
Gabe Wiener - Columbia Univ.     "This 'telephone' has too many shortcomings 
gmw1@cunixa.cc.columbia.edu       to be seriously considered as a means of 
N2GPZ in ham radio circles        communication. The device is inherently of
72355,1226 on CI$                 no value to us." -Western Union memo, 1877
From: lstowell@pyrnova.mis.pyramid.com (Lon Stowell)
Newsgroups: rec.audio
Subject: Re: PNP vs NPN Output Stages
Keywords: Lock
Date: 10 Nov 92 01:51:49 GMT
Reply-To: lstowell@pyrnova.pyramid.com (Lon Stowell)
Organization: Pyramid Technology Corp., Mountain View, CA

In article <1992Nov9.214606.3791@sei.cmu.edu> rsd@sei.cmu.edu (Richard S D'Ippolito) writes:
>
>In article <1992Nov9.113458.16272@EE.Surrey.Ac.UK>, Rob Bish writes:
>
>> ***** if you like Bach use NPN *****
>> ***** if you like Chopin use PNP ***
>> 
>> ...Has anyone else observed this effect, and can they shed any light on the
>> cause?
>> 
>> Rob Bish.
>
>I've noticed the same thing, and furthermore, I get better depth perception
>when listening to baseball and football broadcasts through FETs.
>
   Yes, FET's would have a more "open" and "flat" sound wouldn't
   they.  

   But to really complement the music, you would want to use CMOS.
From: jabbi@anthem.Eng.Sun.COM (Aman Jabbi)
Newsgroups: rec.audio
Subject: Re: How 'bout a new group for the rest of us?
Date: 12 Nov 92 23:12:18 GMT
Reply-To: jabbi@anthem.Eng.Sun.COM
Organization: Sun Microsystems
NNTP-Posting-Host: anthem


>In article <1992Nov12.003105.69226@ns1.cc.lehigh.edu> ptb2@ns1.cc.lehigh.edu (PETER TALAN BERGEN) writes:
>>
>>I could not agree with you more, I am f**cking sick and tired of listening to
>>people ask questions whether they should a stereo for $10,000 or $13,000.  

sour grapes? or is it the socialist bromide enveloping the world today?
if u don't like it, don't read it. if u insist on reading it, re-evaluate 
what u wish to put down on paper before making judgemental calls on 
how much a person is willing to spend on what. It's their own goddam money.


>>I 
>>am personally a little offended that someone would spend that much money on a
>>stereo when there are so many bigger problems today. 

u should be in berkely ;-). Just the kind of lingo that is 
loved here.

In article 21410@news.columbia.edu, gmw1@cunixa.cc.columbia.edu (Gabe M Wiener) writes:

>  As stereo systems go, $10K will buy a good, though not
>excellent system, and one's buying such a system does not preclude one from
>*also* addressing the world's "bigger problems."  Thank you very much.
>
>

And not buying such a system doesn't qualify u as a solver of the "bigger problems".



- Aman

( ..hurt me, punish me, make me listen to mid-fi : Counterpoint button at the CES)
Newsgroups: rec.audio