HDTenEightyP/NetNews huggingface dataset:
From: rsd@sei.cmu.edu (Richard S D'Ippolito)
Subject: Re: power amps blowing tweeters
Organization: The Software Engineering Institute
Date: Thu, 21 Jan 1993 15:33:19 EST


In article <C14v52.6A9@world.std.com>, Richard D Pierce writes:

> In article <1993Jan19.143935.20811@sei.cmu.edu> Richard S D'Ippolito writes:
>>
>>To save you the trouble of calculating the contributions of all of the
>>harmonics, just square the RMS of the squarewave corresponding to the sinewave
>>peak, and you will see that twice the power will be dissipated.  This is the
>>answer you would have arrived at by including all of the expansion terms, 40W
>>in your case, assuming that the impedance was constant with frequency.  Given
>>the inductive nature of the voice coil, the actual power would be much less.
                                                                    ^^^^

> 
> No, it would be a little less, not a lot less. Even at 20 kHz, the
                    ^^^^^^
> inductive component of the inpedance of most reasonable tweeters might
> account for as much as maybe 20% of the total impedance (phase angle of
> the impedance at that point about 10 or 12 degrees.

OK, "much" or "little"?

With your data, here is what I calculate:

freq	wL	tan(th)	theta	Z	cos(th)	Power	SigmaP(n)

20kHz	0.2R	0.2	11deg	1.02R	0.98	~P(nom)	1.0P

60	0.6R	0.6	31	1.17R	0.85	0.24P	1.24P

100	1.0R	1.0	45	1.4R	0.71	0.10P	1.34P

140	1.4R	1.4	54	1.7R	0.58	0.05P	1.39P

Now, using Mr. Frith's base of 20 watts, your impedance ratio data, and
assuming an amplifier power response to 140KHz, we see diminishing
contributions by the fourth term and a "square" wave power of only 27.8 watts
(40% more) compared to the theoretical maximum of 40 (100% more) and his rough
calculation of 37.

So, "much" or "little"?

Rich
From: mortiz@hpprdeb.prd.hp.com (Miguel Ortiz)
Date: Fri, 22 Jan 1993 13:19:36 GMT
Subject: *** HELP! CD MFG. INFO
Organization: HP Puerto Rico Manufacturing Operation
Newsgroups: rec.audio

I am doing a research in CD manufacturing as well as tape duplication. Does 
anyone can provide sources of information about technologies, equipment, costs,
vendors, media suppliers, etc. ?


Appreciate your help in advance,



Miguel Ortiz
E-mail: miguel@hpprdot.hp.com
Phone - 809-882-6437
Newsgroups: rec.audio
From: Jonas.Palm@orgk3.lu.se (Jonas Palm)
Subject: Re: CD Sound under attack again. Was: Re: Preamp and Amp
Followup-To: rec.audio
Organization: University of Lund, Sweden
Date: Sat, 23 Jan 1993 19:09:48 GMT

In article <5494@calmasd.Prime.COM>, jpb@calmasd.Prime.COM (Jan Bielawski)
wrote:
> 
> 	Which reminds me...  An analog tape recorder cannot reliably record 
> more of the frequency spread than about 8 1/2 octaves.  Beyond that range
> the frequency response is probably too low to be called "high fidelity."
> If the tape moves fast one can record high frequencies very well but
> not the low ones as the corresponding magnetic flux with respect to any 
> tape segment changes too slow to magnetize that segment strongly enough.
> If the tape is moving slow then the highs disappear.  No matter what, the
> recordable frequency range is fixed although it can be adjusted up or
> down by choosing the tape speed.
> 
> 	My question is: why aren't CD critics bothered by this?  To me
> it's a serious problem that seems to indicate that the only analog way
> to record is direct to disk.
> 
> 	Jan Bielawski
> 	Computervision, San Diego
> 	jpb@calmasd.prime.com

My best analog tape recorder achieves 20Hz-20kHz +-0.5 dB.
Tested in Real Life, and IMHO, Good Enough. 
(Hell, it even extends quite a bit beyond 20kHz, not that I find it 
particularly useful being effectively deaf beyond 18kHz.)

There are quite a few people in this forum who have experience with 
recording music. I have yet to see any one of them claim that the 
deciding factor in the quality of a recording today is whether the 
music is fed to a digital or an analog recorder in the end.

It would be interesting to hear their opinion of what the limiting
factors usually are in the production of a finished recording, and
how these limitations compare to the limitations at the playback end.

                                          Jonas Palm
From: rsud@sw.stratus.com (Rajiv Sud)
Newsgroups: rec.audio
Subject: Re: CD vs. LP again (was Re: Preamp and Amp)
Date: 27 Jan 93 18:21:43 GMT
Organization: Stratus Computer, Inc.
NNTP-Posting-Host: ernie.cac.stratus.com





In article <7490282@hpfcso.FC.HP.COM>, myers@hpfcso.FC.HP.COM (Bob Myers) writes:
> 
> Rajiv, given that the CD format has been stable for 10 years, how is it
> that "digital" is getting better?  I could see making a claim that the
> analog electronics built into a given line of CD players has improved, or
> that we've seen other improvements in factors outside the format itself
> (equalizations for CD rather than LP, for example) - this is in no way
> "digital" getting better, since all the "digital" portions have remained
> unchanged.
> 
> 
	Yes the format, i.e., sampling rate, has not changed. There's a world
of difference between the cd players of the early eighties and the current
top of the heap designs. And this is in the digital domain (DAC's). Perhaps
you are making a joke of my use of the word "digital" to catagorize all
aspects of the current digital technology applied to audio signal reproduction.

..Rajiv
Xref: sparky rec.audio:19056 rec.video:16206
From: evissch@cad033.NoSubdomain.NoDomain (Eise Visscher)
Newsgroups: rec.audio,rec.video
Subject: Re: Wanted: 8mm/Hi8 stereo VCR info/recommendations
Date: 21 Jan 93 21:48:56 GMT
Reply-To: evissch@scdt.intel.com
Organization: Intel Corp.

In article <1993Jan21.082643.4958@spcvxb.spc.edu>, killeen@spcvxb.spc.edu (Jeff Killeen) writes:
|> In article <1993Jan20.221257.19791@oakhill.sps.mot.com>, kyleh@oakhill.sps.mot.com (Kyle Harper) writes:
|> > 
|> >  I have had little luck finding any selection of 8mm stereo or Hi8 VCRs.
|> >  I do not have much invested in VHS and would like to switch to 8mm for
|> >  recording and archiving favorite movies, etc., and use the Hi-Fi VHS for
|> >  rental playback.
|> > 
|> >  Does anyone out there know if SONY has a reasonably featured, *reasonably*
|> >  priced stereo 8mm or Hi8 VCR? Any other manufacturer?
|> 
|> The Sony EV-A50 8mm VCR is what you are looking for.  It has a tuner plus all 
|> the normal features.  It also has basic editing functions.  Mail order should 
|> be under $500.

Camera World of Oregon has 'em for $350 + $20 S&H. This is not a Hi8 vcr, however,
and does not have stereo.

<stuff deleted>

|> Jeff Killeen - DECUS U.S. Chapter NLC Chair | Email:killeen@eisner.decus.org
|> 
|> DECUS is for folks who are responsible for delivering computing technology.
|> The NLC is the national council for DECUS's Local User Groups - come join us!

-- 
Eise Visscher                                            Design Technology
                                                         (408) 765-5032 RN4-36
Newsgroups: rec.audio
From: ahchan@rd.hydro.on.ca (Arthur Chan)
Subject: Re: Thiele cs2.2 opinions wanted...
Organization: "Ontario Hydro - Research Division"
Date: Mon, 25 Jan 93 15:03:15 GMT

co940@cleveland.Freenet.Edu (Nicholas E. Damato) writes:
: 
: Hello, my neigbor is buying new speakers, he has narrowed his choice
: down to three:
: 1. paradigm studio monitor
: 2. vandersteen 2ce
: 3. thiele cs2.2
:  
: he's got a great quote on the thiele's ($1950) and asked me
: to post hear for opinions (no pun intended...)
: he can't hear them until they arrive, and he has to order
: them first, meanwhile he's got the other two to think about
: so I'm gathering 'experience' for him.
:  
: thank you for taking time to respond (if you do :)
: n.e.d.

A while back, friend of mine and I were looking for speakers.  We listened to
the paradigm and the vandersteens.  We both liked the vandersteens better and
finally bought the vandersteen.  I have not listened to the thiele.  So, I
can't say one way or the other.  But the Stereophile gave a rave review on the
thiele 2.2.  I must say though, the vandersteen 2Ce is the cheapest amongst all
three.  Finally, amongst all the speakers I listened to during that period of
time, I like the Apogee Minor (at one store) the best.  I didn't go for the
Apogee was because I thought they were (rightly or wrongly) difficult to set
up. 

Arthur


-- 
Arthur Chan
Operations Research
KR297 (6173)
Newsgroups: rec.audio
From: kong@leland.Stanford.EDU (Kong Kritayakirana)
Subject: Hifi Equipment Reviewing
Organization: DSG, Stanford University, CA 94305, USA
Date: Tue, 26 Jan 93 21:06:44 GMT

In article <1993Jan26.171403.4001@tc.fluke.COM> strong@tc.fluke.COM (Norm Strong) writes:
>}kong@leland.Stanford.EDU (Kong Kritayakirana) writes:
>}>In article <1993Jan19.172138.29081@bnr.ca> Dave Dal Farra <gpz750@bnr.ca> writes:
>}>>CD may, one day, surpass vinyl as the high-end medium of choice.  
>}>>But not yet.
>}>
>}>How did you arrive at this conclusion? Golden-earing doesn't count.
>}
>}	I don't know what he means by "golden-earing", but I can certainly
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
What I mean by "golden-earing" equipment actually should be renamed 
"undisciplined seeing equipment before hearing it" earing. This is the 
practice done by so many so called "subjective" audio magazines whose
reviewers insist on seeing the brand name and the price of an audio gear
before writing a review. IMO, their way at arriving at how a certain piece
of equipment "sound" is totally meaningless and should be humiliated at.
These magazines sell for fantasy is oftimes preferable to mundane reality.

IMO, there is nothing "subjective" about this type of equipment reviewing.
Yes, if I were to review a hifi piece, what I will do is the following:

1. Put it in my "reference" system. Have its identity (brand name and price)
   concealed.
2. Listen to it at length. 3 years. 5 years. Whatever it takes to burn it
   in according to the manufacturer's tweako suggestion.
3. In the end write a comparison review to whatever reference equipment I
   have on hand.

I doubt whether I can come up with something meaningful. Maybe my ears are
just bad, but at least my common sense and credibility won't get blown away.

The person who originally posted that "CD may, one day, surpass vinyl
as the high-end medium of choice. But not yet." has already retracted his
assertion and declare it as "preference." So I won't make any more comment
on it.
 
>Where I come from, high-end medium of choice means that those who
>consider themselves high-end audiophiles, choose to listen to LP's more
>than any other medium.  Quite frankly, I don't believe that is the case.
>
>Of course, if you define 'high-ender' as someone who prefers LP's, then
>your statement becomes a tautology and is meaningless.
>LP's than to any other medium.  

To me, what's high-end and what's not is like categorizing restaurants into
ones that have "class" and ones that don't. Audio systems can be assembled for
<$1000 or >$1000000. It just depends on where you draw the "highend" line. I
never try to categorize any piece of equipment as "high-end" or "low-end,"
except maybe when I'm joking.

Kong Kritayakirana
From: kirk@hpcc01.corp.hp.com (Kirk Lindstrom)
Date: Wed, 27 Jan 1993 19:24:17 GMT
Subject: Re: CD vs. LP again (was Re: Preamp and Amp)
Organization: Shredding the water of SF Bay, HP-OCD
From: eric@prodigal.psych.rochester.edu (Eric Hansen)
Newsgroups: rec.audio
Subject: Re: books needed about building speakers and amps.
Date: 21 Jan 93 16:57:19 GMT
Organization: University of Rochester - Rochester, New York

In <%MikeW.19.0@canc.byu.edu> %MikeW@canc.byu.edu (M.D. (Mike) Wieda) writes:

>In article <14JAN199310565469@venus.tamu.edu> s0l3906@venus.tamu.edu (LIN, SHYH-HORNG) writes:
>>Subject: books needed about building speakers and amps.
....
>I know of one good source/book on loudspeaker design: David Weems.  I don't 
....
>I don't know where to tell you to find his book.  Try some of the "higher-
>end" bookstores.  If you don't have any luck, email me and I'll get his 


I think Radio Shack carries this book, and also you can get it from
Crutchfield, and Parts Express.  The latter two both have 1-800 numbers,
so just call 1-800-555-1212 (800 dir. assistance).

Good luck

Eric


--
    * Eric J. Hansen                  |    Center for Clinical Computing   *
    *   eric@binoc.bih.harvard.edu    |   350 Longwood Avenue, Boston, MA  *
From: kurts@hpnmdla.sr.hp.com (Kurt Strain)
Newsgroups: rec.audio
Subject: Re: CD vs. LP again (was Re: Preamp and Amp)
Date: 26 Jan 93 16:33:30 GMT

In rec.audio, lstowell@pyrnova.mis.pyramid.com (Lon Stowell) writes:

>      If any of these tactics sound like TV evangelists, its no
>      wonder, the ability of the human mind to fool itself and
>      attempt to spread the ignorance is amazing.   

You make us roll with laughter.
Newsgroups: rec.audio
From: gfl@herahera.cc.bellcore.com (lenahan,grant f)
Subject: Re: CD vs. LP again (was Re: Preamp and Amp)
Organization: Bellcore, Livingston, NJ
Date: Mon, 25 Jan 93 17:32:44 GMT

In article <24694@alice.att.com>, jj@alice.att.com (jj, curmudgeon and all-around grouch) writes:
> In article <1190792@hpnmdla.sr.hp.com> kurts@hpnmdla.sr.hp.com (Kurt Strain) writes:
> >Gee, sorry I follow what I hear, and I don't buy these overrated garbage
> >technical arguments that you believe is proof for the disqualification
> >for the medium as a serious contender. 

I'm impressed.  I can't quite parse that sentence.  Are all the
verbs properly conjugated? :-) :-)

Grant
( cowering under his laptop, hoping no one will attack him next ....)


Xref: sparky rec.audio:19091 rec.video:16224
From: lstowell@pyrnova.mis.pyramid.com (Lon Stowell)
Newsgroups: rec.audio,rec.video
Subject: Re: Sony TA-E2000ESD DSP A/V Surround Preamp
Date: 22 Jan 93 02:57:08 GMT
Reply-To: lstowell@pyrnova.pyramid.com.pyramid.com (Lon Stowell)
Distribution: rec
Organization: Pyramid Technology Corporation

In article <C17zCv.Awv@ampex.com> dna@ampex.com (David Altekruse) writes:
>>
>I'm not sure I follow your question.  There are ten user programable 
>selections so you can set the equalization on any or all of them.  You
>can disable the other DSP functions on any of them, of course, leaving
>one of them just for equalization, if you want.  If you want the same
>equalization on all selections you do have to program each one of them
>separately which is more work than ideal.  
>

  The TA-1000 doesn't allow you to EQ the rear channels yourself.
  You are stuck with Sony's literally tin ears if you use much
  reverb.
From: shetline@bbn.com (Kerry Shetline)
Newsgroups: rec.audio
Subject: Re: What happen to dbx?
Followup-To: rec.audio
Date: 23 Jan 1993 16:27:36 GMT
Organization: BBN
Distribution: world
NNTP-Posting-Host: bbn.com

In article <C1B6C9.D20@world.std.com>, DPierce@world.std.com (Richard D
Pierce) wrote:
> DBX pro equipment is alive and well and living under the auspices of AKG
> Acoustics. There are some 20-25 products in the line including noise
> reduction systems, compressor/limiters, equalizers, and so on.

The company also had a hand in the design of the American standard for
Multichannel Television Sound, otherwise known as MTS, or just plain TV
stereo. They designed the noise reduction system used for the stereo
subcarrier. This noise reduction allows stereo TV to function with very
little noise difference as compared to mono, unlike FM broadcasts.

I believe that Zenith was the other company involved in creating the MTS
standard with dbx.

-Kerry
From: jeh@cmkrnl.com
Newsgroups: rec.audio
Subject: Re: surround sound recording on VCR
Date: 26 Jan 93 03:55:50 PST
Distribution: usa
Organization: Kernel Mode Systems, San Diego, CA

In article <74363@cup.portal.com>, gb@cup.portal.com (Greg A Buechler) writes:
> I have a high-fi VCR that plays surround sound movies quite well, but I 
> seem to not be able to record a surround sound show off the TV and get
> the effects.
> 
> Any suggestions?

You are of course aware that a VCR does not record "off [from] the TV".  Let's
say "record from the cable" or "record from the antenna", or, generically,
"record from the RF input". 

That nit having been picked... 

- are you certain that the VCR has MTS stereo as well as VHS HiFi ?  I've 
never heard of a HiFi VCR that didn't have MTS... but I suppose it's possible.
In the absence of an MTS stereo tuner, the VCR won't record stereo from its
RF input.  And of course without stereo, there's no surround either.

- MTS VCRs (like MTS TVs, and stereo tuners for that matter) often have a
"stereo/mono" switch.  Make sure this is in the "stereo" position.  

- Make sure that the "stereo" or "MTS" indicator is lighted when recording a
program that's in stereo.  (The local tv station may not be sending it in
stereo.  If no stereo, then no surround.  Or, some cable systems don't provide
stereo, even though the off-the-air signal they're relaying is in stereo.) 

Given all of that, your VCR should be recording stereo from the RF input.  
There is no special trick to recording surround sound -- if you record 
stereo, you're also recording any surround information that's along for the
ride.

- on playback, check for stereo effects.  Note that very few stereo VCRs will
provide MTS stereo via the RF output jack.  (I'm tempted to say "none", but
since I don't have a definitive list of the features of every VCR ever made, I
won't go out on that limb!)  To get stereo playback you need to use the "audio
line out" jacks on the VCR, and feed these to a stereo amp + speakers, or feed
the video and audio line jacks to the line inputs on a stereo tv or monitor. If
you're not sure, the best way to check for stereo sound effects (but not
surround) is with headphones.  (You are probably doing this part right, since
you're getting stereo and surround from pre-recorded (movie) tapes; I just
mentioned this to be complete.) 

Finally...

- most of the surround effects I've heard from tv programs are pretty subtle. 
Are you certain that they're missing?  eg on Star Trek:TNG, the "surround
track" is pretty much limited to things like the engine "rumble" on shipboard
scenes.  On Batman: TAS, I've noticed the surround track being used for crowd
noises and the like, and not much else.  (Commendably imo; having the apparent
source of sounds bounce all over the room can be damned distracting.)  

The thing to do is to find a movie that's being broadcast that you know was
done in surround, tape it off the air, and compare it to a rental tape. 

	--- Jamie Hanrahan, Kernel Mode Systems, San Diego CA
Internet:  jeh@cmkrnl.com, or hanrahan@eisner.decus.org  Uucp: uunet!cmkrnl!jeh
From: v114qgu3@ubvmsd.cc.buffalo.edu (Henri Defense)
Newsgroups: rec.audio
Subject: Dolby S vs. DCC etc.
Date: 26 Jan 93 22:50:00 GMT
Organization: University at Buffalo
News-Software: VAX/VMS VNEWS 1.41


	Almost a year ago, I remember reading a Stereo Review article on Dolby
S: a few audiophiles were given blind ABX listening tests to see if they could
tell the difference between CD and Dolby S.  I seem to recall that when the
listeners were given classical pieces (sans piano solos) and "modern" music,
they could not hear a difference almost half of the time.  Apparently, this
seems to be better than DCC or MD's record, seeing as how many people claim they
can hear a difference between PASC/ATRAC and CD most of the time.  This leads to
my question: Ignoring the fact that Dolby S is an analog format, which sounds
better... Dolby S, DCC, or MD?  (If anyone has listened to Dolby S, I'd love to
hear your reaction.)  Thanx.
Newsgroups: rec.audio
From: ledzep@cbnewsh.cb.att.com (carl.w.muhlhausen)
Subject: Re: Denon or SonyES?
Organization: AT&T
Date: Wed, 27 Jan 1993 15:26:29 GMT

In article <199301221401.AA24054@europa.eng.gtefsd.com> whiting@europa.eng.gtefsd.com (claude whiting) writes:
>Newsgroups: rec.audio
>Subject:Denon or Sony ES? 
>References: 
>Reply-To: whiting@europa.eng.gtefsd.com (claude whiting)
>Followup-To: 
>Distribution:usa 
>Organization: GTE Federal Systems
>Keywords: 
>
>I may be purchasing a new cd player shortly and have narrowed my choices down 
>to two manufacturers and three models. These are: 
>
>Sony CDP-X339ES 
>Denon DCD-1560
>Denon DCD-2560
>
>Does anyone own one of these? What are your experiences? The Sony seems to be 
>extremely well built...the Denons less so. Is Denon reliable?

I've had a Denon 1560 for two years now with no problemos. I'm
very impressed with the sound, reliability, and build quality.
Of course the Krell (?) that's built into a block of
granite might be nice.
In what ways do the Sony's seem better built?

I considered the Sony 33ES when I was shopping, but it didn't
have some of the features that the Denon had. (Optical and
variable line level out jacks as I recall).

Carl

Carl Muhlhausen		"Kum wit me iff you vant to liff"
att!taz!ledzep		 
Newsgroups: rec.audio
From: phamtom@seas.gwu.edu (Dzung L. Pham)
Subject: Trying to order CS8412 S/PDIF
Organization: George Washington University
Date: Mon, 25 Jan 1993 18:02:03 GMT

Hello,

I'm trying to order the Crystal Semiconductor CS8412 S/PDIF chip for a
DAC I'm building but a place I've talked to requires I order at least four
chips since the minimum order is $100.  I've found one other person (Kong)
who would be willing to get one with me so I need two other people.  The
chip costs about $25 each and has a much lower jitter specification than
the Yamaha chip.

If someone knows a distributor who will sell in quantity of one, I'd
appreciate that information.  Reply via e-mail to my GW address or
just post a followup.

Thanks a lot,

   -- Dzung Luu Pham

   The Applied Physics Laboratory  or  The George Washington University 
   (dzung_pham@jhuapl.edu>	       (phamtom@seas.gwu.edu)	

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Newsgroups: rec.audio
From: karty@cs.washington.edu (Richard Karty)
Subject: Could a CD be played backwards, or slower?
Organization: Computer Science & Engineering, U. of Washington, Seattle
Date: Thu, 28 Jan 93 00:15:07 GMT

Some idle speculation...

Question #1:

I am wondering if a CD could be played backwards.

Here is what I've been thinking:

(N.B. I have only a lay understanding of the technology. I don't even
know if I'm using the word 'bit' properly. So please bear with me!)

Let's assume the motor and so forth could be easily reversed. Now a
bit of digital information that was, say "1010011" on the CD, (which
encodes the number 83, right?) would come out as "1100101" - which is
totally different.

So lets say the CD player could be designed to reverse the binary
digits of each "bit" (number/group/chunk/whatever it's called) so that
it is read correctly, but it would start with the last bit and proceed
to the first. 

What would that sound like? Like an analog tape or record being played
backwards? 

Question #2:

What would you hear if you slowed down a CD?

 - if you slowed down the speed of rotation, or the sampling rate, or
both?

Thanks for any ideas you may have on this. If you think it's
inappropriate to take up space on rec.audio with this subject, please
respond by e-mail.