HDTenEightyP/NetNews huggingface dataset:
From: mbk@lyapunov.ucsd.edu (Matt Kennel)
Newsgroups: rec.audio
Subject: Re: How can different digital cables sound different?
Date: 6 Jan 1993 23:11:41 GMT
Organization: Institute For Nonlinear Science, UCSD
NNTP-Posting-Host: lyapunov.ucsd.edu
X-Newsreader: Tin 1.1 PL3

igb@fulcrum.co.uk (Ian G Batten) writes:
: More importantly, there is no clock.  The clock for the DAC is recovered
: from the SPDIF datastream.  Jitter in that link will cause on the time
: axis the same problems as quantisation errors on the voltage axis: a
: source of error between the sampled and the reconstructed waveforms.

"recovered" how?  I suspect strongly that any circuitry is going to
effectively low-pass the "jitter" in the clock base out of audibility.

: ian

--
-Matt Kennel  		mbk@inls1.ucsd.edu
-Institute for Nonlinear Science, University of California, San Diego
-*** AD: Archive for nonlinear dynamics papers & programs: FTP to
-***     lyapunov.ucsd.edu, username "anonymous".
From: allana@hpmwtd.sr.hp.com (Allan Armstrong)
Newsgroups: rec.audio
Subject: Re: How can different digital cables sound different?
Date: 8 Jan 93 17:00:50 GMT
Organization: HP Santa Rosa Site (SRSD MWTD)

>>    Most commercial circuits I know of a 0 is at least 0.7 volts or
>>    more...as that's the saturation of silicon.
>
>Apparently the commercial circuits you know don't include anything based on
>CMOS logic, which is the basis for most modern LSI circuitry.  0.7 volts is
>not the "saturation of silicon".  Rather, it is the saturation voltage (base-
>emitter junction voltage) of a silicon junction transistor.  A (silicon)
>MOSFET transistor as used in CMOS circuitry typically swings almost
>rail-to-rail (from about 0.2 volts to about 4.8 volts) as opposed to the 0.7
>to 2.8 volt swing which is more typical of TTL style logic.

Just to set the record straight...

The typical low voltage of TTL logic is about 0.2 Volts, which is Vcesat of
a typical low-power Si BJT. 0.2 Volts is the "saturation of silicon."
Vbe, on the other hand is the forward voltage of the b-e junction and is
completely unrelated to Vcesat.

Otherwise, everything the second poster said is right.

If you're interested, Vbe and Vcesat vary with technology. Here's an
incomplete table of them:

technology   Vbe Vcesat
Ge BJT       0.2 ?
Si BJT       0.7 0.2
power Si BJT 0.7 0.7
Si-Ge HBT    ?   ?
GaAs HBT     1.4 0.6
InP HBT      0.6 ?

Allan
Xref: sparky rec.audio:18344 misc.forsale:35246 ny.forsale:2313
From: fnox@vax5.cit.cornell.edu (Mark L. Margolis)
Newsgroups: rec.audio,misc.forsale,ny.forsale
Subject: For Sale - Parasound HCA-800II
Date: 12 Jan 93 21:59:54 EST
Distribution: misc,rec,ny
Organization: Cornell University

For Sale:

Parasound HCA-800II 100wpc power amp
About 1 month old

Reason for selling: Got a very nice gift for the holidays,the HCA-2200
(Parasoundd's top-of-the line amp)

Anyhoo, selling the 800 for $325 +S&COD

- 

******************************************************
*                                                    *
*   Mark Margolis     FNOX@VAX5.CIT.CORNELL.EDU      *
*                     FNOX@CRNLVAX5.BITNET           *
*                                                    *
*   Cornell University - Ithaca, New York 14853      *
*                                                    *
******************************************************
 
Newsgroups: rec.audio
From: monitn@rebecca.its.rpi.edu (Nicholas Monitto)
Subject: Re: Info on Sony receiver wanted
Distribution: na
Date: Tue, 5 Jan 1993 08:41:44 GMT

hm002b@uhura.cc.rochester.edu (PRIMUS SUCKS!) writes:

>In article <1i9q4iINN75g@gaia.ucs.orst.edu> creasyg@ava.bcc.orst.edu (Glen Creasy) writes:
>>Howdy folks!
>>
>>I recently bought a Sony STR-AV1070X from Silo.  It was a demo model,
>>so I didn't get anything but the unit and the remote.  The sales-
>>lady said that I could call Sony and order a manual for it.
>>
>>Does anyone have an address to write to or a phone number to call
>>to order an owner's manual for it?

>1-800-222-SONY

>>
>>Also, if anyone has any comments about this model, I'd be interested
>>in hearing them.  I have it hooked up for ProLogic, and it sounds
>>pretty good (..vast understatement :-).  
>>
>>One thing I'm slightly concerned about is some clicking noises coming
>>from the surround speakers when I adjust their volume.  One click for
>>each push of the volume button.  The graphic equalizer also jumps 
>>all the way across the band when I do this.  Are these noises normal?
>>

I own an STR-AV1070, and this sounds similar to my problem. A relay (or 
something of that nature) will keep tripping when the unit's on, and sometimes
when it's off. When the volume is changed from the remote, it clicks out of its
cycle, and sometimes powers off and on. I am trying to get this fixed.

The graphic eq (or more accurately, the Real-time analyzer) will jump when you
change the volume by remote. Remote volume is driven by a small motor, and the
RTA picks up the noise of this motor running. This is a minimal problem.

>>Also, there is a bit of hiss coming from the surround speakers (rears
>>and front).  Is this a normal byproduct of the ProLogic electronics?

>I am not sure if the hiss is normal? On my 1090 I get hiss when I turn it up
>REAL loud otherwise it is very clean. I do not get those clicks either.

From discussion some time ago in this newsgroup, the noise in the surround
channels was a common affliction in the xx20 and xx70 lines. I think mine had
it too, since the first time I brought it to the shop, it came back with the
same relay problem, but they changed an IC and the surround did seem better.

Nick
monitn@rpi.edu

>PS
Newsgroups: rec.audio
From: eomiya@borland.com (Elliot Omiya)
Subject: Re: "Stubby" RCA cables avail?
Originator: eomiya@genghis.borland.com
Keywords: audio cables
Organization: Borland International, Inc.
Distribution: usa
Date: Wed, 13 Jan 1993 00:55:09 GMT


A few people e-mailed me (thanks a lot!) and informed me that Radio Shack
sells right angle RCA jacks.

-=<EHO>=-

Newsgroups: rec.audio
From: a2lau@undergrad.math.waterloo.edu (Alan Lau)
Subject: Denon pre-amp, amp
Organization: University of Waterloo
Date: Fri, 8 Jan 1993 15:12:46 GMT

Any reviews on the Denon PRA-1500 pre-amp and the P0A-2800 power amp?
Any other suggestions compatible with these products?
ie. daisy chain, bridgable, remote control, good overall system
    and reputation.

From: joncon@hpcc01.corp.hp.com (Jon Connolly)
Date: Mon, 11 Jan 1993 17:33:11 GMT
Subject: Re: speakers out of back of van sellers arrested
Organization: the HP Corporate notes server
Newsgroups: rec.audio

A friend of mine was approached by two guys in a white van, as I have been
many times, and at the time  needed some speakers.  He happened to be 
moving and most of his possesions had been moved from his old place 
except for his  home stereo among other things.  He invited these guys 
over to his old place to try the speakers out.  He tested them and they
turned out to be decent speakers.  This was about ten years ago and I 
don't think he has ever had a problem with them.  Of course, for the
true audiophile these speakers aren't the answer but for the average
stereo system they were very adequate and handled  a respectable amount
of power.

I don't know for sure but I think that there is a company or companies
that has adopted this type of tactics as their marketing scheme.  The 
reason I think so is that I have seen too many of these mysterious 
white vans selling speakers.  They always have the same line and it's
never the same two guys.  I think they may get sales from the people 
that believe that they are getting a great deal because the merchandise
is being sold out the back door.  When in actuality the whole thing
*may* be totally legit and rather than you going to the retailer they
come to you.

I don't really know, this is just my theory of a possibility, so 
don't  hold me to it.

I would definitely beware of any one selling merchandise that way.
From: curt@oasys.dt.navy.mil (Curt Welch)
Newsgroups: rec.audio
Subject: Re: MiniDisc is here!
Date: 5 Jan 93 04:34:28 GMT
Reply-To: curt@oasys.dt.navy.mil (Curt Welch)
Organization: Carderock Division, NSWC, Bethesda, MD

In rec.audio, deraadt@newt.cuc.ab.ca (Theo de Raadt) writes:
>I mean, if you stored uncompressed digital information on an MD, how many
>megabytes would it hold?

I posted a long article about this a week or so ago (which I didn't save).
The answer is about 130 Meg.

Curt Welch
From: al@qiclab.scn.rain.com (Alan Peterman)
Newsgroups: rec.audio
Subject: Re: How to make CD output OK for input as "Phono"?
Keywords: Resistors and cables and crimpers (oh my!)
Date: 10 Jan 93 18:32:00 GMT
Article-I.D.: qiclab.1993Jan10.183200.24736
Organization: SCN Research/Qic Laboratories of Tigard, Oregon.

In article <1993Jan10.171601.13626@news.stolaf.edu> carlsonb@mari.acc-admin.stolaf.edu (Bradley P Carlson) writes:
>I'd like to use the line-level output from my CD player as input to my
>amp's "Phono" selection.  I've heard that this can do damage, since
>many amps expect a lower line-level input from a turntable.  Can the
>CD signal be lowered easily, maybe by using in-line resistors?  If so,
>any guesses as to proper resistance?

The problem is not just level, but also equalization.  The line level
signals from your CD player are nominallly around 1 volt, a magnetic
phono is spec'd at about 3mv - so you need to drop the signal by
about 1:300.  The other problem is that the phono signal is
equalized by a rather severe high cut - and I believe some low
frequency eq also..defined as the RIAA equalization.  This will
require some RC networks.

Switchcraft used to make some neat little adaptor plugs for doing just
what you wanted...but it was in the 60's and they are not available
at this time.  They were aimed at using crystal/ceramic cartridges
into magnetic phono inputs and cost about $1.77.  Model was called
a 328A Adaptor.  I think they should make them again...


-- 
Alan L. Peterman                                 (503)-684-1984 hm & work
                       al@qiclab.scn.rain.com
It's odd how as I get older, the days are longer, but the years are shorter!
From: shetline@bbn.com (Kerry Shetline)
Newsgroups: rec.audio
Subject: CD anti-skip buffer (Was: Re: Stereo Review's critical judgement)
Followup-To: rec.audio
Date: 5 Jan 1993 14:45:22 GMT
Organization: BBN
Distribution: world
NNTP-Posting-Host: bbn.com

In article <C0DBEE.4An@CAM.ORG>, pascal@CAM.ORG (Pascal Gosselin) wrote:
> Is there a CD player on the market with large read-ahead buffer (a-la-
> minidisk) that will prevent skipping? It is so simple, I wonder why
> nobody seems to have done it yet for CDs.

There is one Sony CD-walkman that has an anti-skip buffer. I just wish that
a few car models would become available!

-Kerry
Xref: sparky rec.audio:18099 rec.video:15634
From: chen@digital.sps.mot.com (Jinfu Chen)
Newsgroups: rec.audio,rec.video
Subject: Re: Selecting an LD Player
Date: 7 Jan 93 18:13:55 GMT
Followup-To: rec.audio
Organization: Motorola, LICD, SPS, Mesa, AZ

In article <1993Jan5.213214.22575@lsican.uucp> michael@Canada.lsil.com writes:
>Has anyone on the net actually taken the digital output from a CD player and
>pumped into a home PC and compared the output with and without the "green pen",
>the "CD rings", and all of the other "send-your-money-now" add-ons that have
>appeared for CDs?  A bit-by-bit comparison would rule out any differences in the
>bit-stream using these gadgets, and leave transport related issues adding to
>the room noise.

I used to believe this bit-is-bit too until reading Stereophile recent
article in jitter and basic theory of digital to analog conversion.  People
who believe bit-by-bit comparision can prove accurate D/A conversion simply
forget another important factor, timing, that is also important for accurate
conversion.

Having said that I have to say I haven't tried any of those tweaks and tend
to not to believe they will work.  I just want to point out bit-by-bit
comparsion only proves half of the picture is correct.
From: w0s7835@tamsun.tamu.edu (Won Sohn)
Newsgroups: rec.audio
Subject: Normal or Not(Charged Voltage)
Date: 12 Jan 1993 12:06:48 -0600
Organization: Texas A&M University, College Station, TX
NNTP-Posting-Host: tamsun.tamu.edu
Summary: remained voltage in preamp.
Keywords: preamp, charge

Hi, netters.
I have some questions about the power supply section of the preamplifier.
The pre-amp is PF-C9 with 12 tubes(if anybody knows about this product,
please make me more knowledgable) and its power supply section is solid state.

While I am trying to improve its volume controls(potentiometers), I found out
the charged voltage in my pre-amp is not trivial( the charged voltage broke
my potentiometers).
The measured voltage from the huge capacitors (10,000 uF 25V, 40 uF 250V) was
around 200V(275V in operating status) and it was measured around 5 hours after
turning off AC power(actually I pulled out AC power cord before the improving
job).

Now, first question is "is this normal or not?".

After assuming this is not normal, I thought about adding discharging loop
by connecting a resistor parallel to each capacitor.
Second question is "what kind of resistor(material, value, wattage) is
reasonable for this purpose?".

Any comment or suggestion will be appreciated.

Thanks.

	Won Sohn	e-mail: sohn@ee.tamu.edu
 
From: kirk@hpcc01.corp.hp.com (Kirk Lindstrom)
Date: Mon, 11 Jan 1993 17:19:50 GMT
Subject: Re: Losing My Religion (Was...many times tangentially removed)
Organization: Shredding the water of SF Bay, HP-OCD
From: roth@3d.enet.dec.com (Jim Roth)
Newsgroups: rec.audio
Subject: Re: Losing My Religion (Was...many times tangentially removed)
Date: 11 Jan 93 22:02:50 GMT
Organization: Digital Equipment Corporation


In article <gmaltby.54.726742835@unpcs1.cs.unp.ac.za>, gmaltby@unpcs1.cs.unp.ac.za (Gavin Maltby) writes...

>My Wadia X32/3200 combination CD player supports all the interfaces.
>I started with the coax link.  I paid a fair bit for that high quality
>coax.  At the time the DAC had toslink receiver electronics installed,
>in addition to the coax link.  Comparing the two gave no conclusive
>evidence, even in a rather revealing system.  I could not justify the
>expense, really.  A friend with the same CD had the AT&T receiver
>electronics installed, and we did a comparison.  With the transport
>next to the rest of the system things were better, but not massively
>so.  Then we removed the transport to the next room (using the 6m
>optical cable).  The difference was amazing, as though we'd changed
>some major component.  I have since installed the AT&T stuff on my
>DAC, and have similar results.  It seems that the biggest, and definitely
>worthwhile, difference was getting the transport out of an area where
>it could be vibrated.

My only comment is that it reflects sheer incompetance in the design
somewhere along the line with those components if moving the
CD transport elsewhere really makes a genuinely "amazing" difference
due to vibration.  For the money Wadia and their ilk are charging,
there is no excuse.

Actually, tests I did ages ago with a few fairly inexpensive CD players
where I notched out a sinewave and played the residual over speakers
while I jarred and shook the players showed virtually no microphonics
or other effects that could be attributed to jitter.

Perhaps you should check again, if mere belief that the transport has
been located to another room makes an "amazing" difference.

- Jim
Newsgroups: rec.audio
Subject: Re: How do 1 bit (or bitstream) CD's work?
From: deanaj@elec.canterbury.ac.nz (A. J. Dean)
Date: Mon, 11 Jan 1993 04:05:41 GMT
Organization: Electrical Engineering, University of Canterbury, New Zealand
X-Newsreader: TIN [version 1.1 PL6]

Edward Walsh (edw@boi.hp.com) wrote:
: So how do 1 bit players work? So far I have only received vague answers.
: It doesn't appear to be in the FAQ, and I have missed any answers about
: this that might have been given in this group. So far the only insight I
: have is that it might involve pulse width modulation and a counter. This
: still doesn't answer what would be done with the pulse width modulated
: signal to get audio out, or how the pulse width is determined in the
: first place. A counter would have to have a mighty speedy clock. Thanks
: for any insights.

I've run out of time today for a detailed description, but:
You're on the right track. The PWM is not done at a regular frequency,
however, it's more like PWM by noise than a triangle wave. However, the low
frequency result is the same (ie audio cf 11MHz). Another difference (the
main one), the 'PWM' signal is _not_ intended to be reproduced flat, but
passes through an integrator first (ie rather than filtering it for a flat
response in the audio band and rolling off above that, everything rolls off
at 6dB/oct from 10Hz to 20MHz...). To produce the 1-bit bitstream you could
I suppose PWM the differential of the signal by noise (dither) but Philips
use a delta-sigma approach I think.

They have to use this approach (the integrator) when you think about it,
because their bitstream comes out a a rate of approx 11MHz. At 44.1kHz this
gives about 250 bits per sample which is a resolution of around 8 bits (if
it is filtered by a linear system). With the integrator the resolution is
still 8 bits, but the maximum output level at HF is lopped back rather than
raising the noise floor 45dB or so. "Won't that screw up the sound?" I hear
you say (well, I don't but use your imagination...). Surprisingly enough (or
obviously enough if you have listened to one) it doesn't, because those
large sample to sample amplitude changes just don't exist (much) in music.
Whether a bitstream converter robs you of too much information is up to your
ears though.  

Now Philips aren't necessarily going to like this, but you know how they
pushed their bitstream chip (SAA3250 or somehthing) as something
revolutionary in their ads (they did here), striving for perfection, etc
etc? Well, in the data book it says (amongst that there could be some
improvements in sound) that the chip's advantages were that it was cheap to
manufacture, cheap to implement, cheap to solder etc etc. There is a 4*
oversampled data output so users can choose to replace the bitstream section
with a "high quality 16 bit DAC"! Talk about marketing hype. Nevertheless,
the concept is so cheap that less 'real' corners have to be cut, resulting
in what can be a pretty brilliant DAC despite its low cost.  

So much for "I've run out of time today..."!!!

Antony. (deanaj@elec.canterbury.ac.nz)
Newsgroups: rec.audio
From: Frank@mindlink.bc.ca (Frank I. Reiter)
Subject: Re: Sony STR-790 speakers in series
Organization: MIND LINK! - British Columbia, Canada
Date: Wed, 6 Jan 1993 19:26:33 GMT

> Jerry Whelan writes:
>
>         The only problem with this analysis is that Sony amplifiers
> (at least in the STR series) connect the A+B speakers in series,
> not in parallel.  Don't believe this weirdness?  Try it yourself,
> hook up only the A speaker pair and set switch to A+B, there will
> be no sound on a Sony and plenty of sound on most any other brand
> of amplifier.

This is documented in the manual (at least for the 990).  I suppose a
positive side effect is that the amp should have no trouble running four <8
ohm speakers.

Frank.
--
___________________________________________________________________
Frank I. Reiter                 Internet: Frank@mindlink.bc.ca
MIND LINK! Communications Corp. Surrey, British Columbia, Canada
Newsgroups: rec.audio
From: surtij2@aix.rpi.edu (Johan Surtihadi)
Subject: Dynaco PAS2 schematic diagram wanted
Organization: Rensselaer Polytechnic Institute, Troy NY
Distribution: usa
Date: Wed, 6 Jan 1993 19:20:23 GMT

Hi:
I have an old Dynaco PAS2 preamp built from the kit. I would like to do some
upgrading and modification. However, I don't have the schematic diagram and
the kit instruction manual. Would someone please share those copies with me?
I will recompense you for the postage and photocopying or whatever.
Thanks.
#
Newsgroups: rec.audio
From: chiu@gpb-mac.sps.mot.com (Norman Chiu)
Subject: Re: Stereo Review's critical judgement
Followup-To: rec.audio
Organization: Motorola Inc.
Date: Wed, 6 Jan 1993 18:59:55 GMT

In article <C0CEJH.82o@CAM.ORG>, pascal@CAM.ORG (Pascal Gosselin) wrote:

> You see, CD is very simple. 16bit audio samples (linear) played back
> at 44.1Khz. Now, each 16bit value corresponds to a particular voltage
> level, which makes the sound we hear.  As long as the D/A converter is
> linear, the sound will be essentially perfect.
  ^^^^^^
You just answered your own question of why people buy $1000+ CD players.
In the real world, there is NO perfectly linear D/A converter but only
close approximations of it.  With our current techology, the DAC found
on most modest-priced CD players are very linear, very good.  So with the
more expensive CD players, the DAC gets (hopefully) closeR to the
theoretical absolute linearity.  However the law of Diminishing Rate of
Return holds such that the closer the DAC approaches this absolute
linearity, the more astronomically expensive it becomes.

> As for those of you buying $1000+ CD players, I'm afraid you are getting
> taken for a big, expensive ride.

But you really can't blame people for trying to attain absolute perfection,
can you? :-)

   /|   /  chiu@gpb-mac.sps.mot.com  | Norman Chiu - Motorola Inc.
  / |  / ___________________________ | "We never gonna survive
 /  | / /  / /__/  /\/\   /_\   /| / |  unless we get a little
/   |/ /__/ /   \ /    \ /   \ / |/  |  crazy"       - Seal
From: kega@nobeltech.se (Kent Gabrin)
Newsgroups: rec.audio
Subject: PASC/ATRAC article in HIFI NEWS
Date: 5 Jan 93 09:09:41 GMT
Organization: NobelTech AB

About PASC, ATRAC, DCC and MD I just read, in my opinion, a well
written article in the november (1992) issue of the UK magazine "HI FI
NEWS Record Review". The article was written by Peter J Comeau and was
labeled "Does data compression work?"

The article describes and compared the differencies between the two
types of compression (PASC & ATRAC) and gave me a lot of answers.

Regards Kent

Kent Gabrin   NobelTech Systems    ! My thinking is not as great as
S-175 88 Jaerfaella      Sweden    ! Oliver Berendinus Bumble /Will Try
KEGA@nobeltech.se ! DAT owner since jan 1992
Newsgroups: rec.audio
From: law40001@nusunix1.nus.sg (CHENG KWONG WING)
Subject: Re: WANTED: Indoor FM antenna advice
Organization: National University of Singapore
X-Newsreader: TIN [version 1.1 PL6]
Distribution: usa
Date: Mon, 11 Jan 1993 05:55:19 GMT


You could try a brand called "Parsec" too.

I have seen it around in a shop here, but I have no idea whether it is
good or not.  (Doesn't look too bad though.)

Hope it helps.


--
--
email: law40001@nusunix1.nus.sg or law40001@nusunix3.nus.sg

____________________   .    .   __         . 
\______NCC_1701_____|) .____.--"--"---._____ 
             ||      /-----._________.----/  
     /=======||====/___/       "--"          
   . \==\____________|(-                .
From: wart@cco.caltech.edu (Michael L. Thomas)
Newsgroups: rec.audio
Subject: DAT Recommendations
Date: 4 Jan 1993 07:36:14 GMT
Organization: California Institute of Technology, Pasadena
NNTP-Posting-Host: sandman.caltech.edu

I am now in the process of looking for a DAT deck for my stereo so that I
can convert all of my records to the no-wear-and-tear digital format  (I
know, analog is better, but I can't afford to play my $40 records over
and over).

All that I have seen so far is the Sony 7?? model at the Good Guys in 
Pasadena.  I was wondering if anyone knew of any place in the LA area
that sold a Denon or Philips DAT deck (not portable.  I'd rather have the
whole component).  Or, if anyone could recommend a reasonably priced ( < $800)
good DAT deck, 	I would appreciate it.

--Wart