HDTenEightyP/NetNews huggingface dataset:
From: eisenhof@zax.eda.teradyne.com (Karl Eisenhofer)
Newsgroups: rec.audio
Subject: Re: Where can I find the Nyquest theorem
Date: 27 Aug 92 15:57:32 GMT
Reply-To: eisenhofer@maven.dnet.teradyne.com
Organization: Teradyne, Inc. Boston MA

In article <1992Aug25.200552.12909@fcom.cc.utah.edu> dave@news.ccutah.edu (dave martin) writes:
>Where can I find the exact statement of the Nyquest theorem?  I have seen
>some articles attributing certain properties of digital audio to the Nyquest
>theorem which happen to be false.  I am trying to find out if the theorem
>is in error (unlikely) or if the author of the piece I read is wrong (more
>likely).
>
>dave@csulx.weber.edu
>DMARTIN@CC.WEBER.EDU


This is quoted from _Commuication Systems_ by Simon Haykin (without
permission of course).  There are two versions of the theorem provided:

	1) A band limited signal of finite energy, which has no frequency
	   components higher than W hertz, is completely described by
	   specifying the values of the signal at instants of time separated
	   by 1/2W seconds.

	2) A band limited signal of finite energy, which has no frequency
	   components higher than W hertz, may be completely recovered from
	   a knowledge of its samples taken at the rate of 2W per second.

This is known as the sampling theorem, or the Nyquist theorem

Music, obviously, is not a band limited signal.  This is where it gets tricky
around digital recording since aliasing of the higher frequency components
can easily occur.  This is also the arguement that is used by those who claim
that analog sounds better than digital (i.e. they claim that the higher 
frequency components add something to the sound that digital recording either
can't capture and reproduce, or that digitizing the signal aliases these higher
frequency components down to lower frequency components that humans can hear).
Another factor contributing to aliasing is the fact that a signal cannot be
finite in both time and frequency.  This violates that strict band limiting, and thus
aliasing will always occur in time limited signal sampling (and thus in
every signal that is digitized for a digital recording, there will be aliasing)
To combat these effects, there are two corrective measures

	1) Prior to sampling, a low pass pre-alias filter is used to attenuate
	   those high frequency components of the signal that lie outside of the
	   band of interest.

	2) The filtered signal is sampled at a rate slightly higher than the 
           Nyquist rate.

Number 2 is why the sampling rate for DATs is what it is (I forget the
exact number) instead of simply 40,000 samples per second (twice 20,000 Hz).

I hope that this answers your question, plus lots that you did not want to
know :-)

Karl

-- 
Karl Eisenhofer  SPIKE  eisenhofer@maven.dnet.teradyne.com
"Searchlight casting for faults in the clouds of delusion"
From: hess@hpdmd48.boi.hp.com (Kevin Hess)
Newsgroups: rec.audio
Subject: Re: Broken Tap Removal Summary
Date: 28 Aug 92 18:14:45 GMT
Organization: Hewlett Packard - Boise, ID

> In late July, I asked for suggestions on how to remove broken taps from
> an aluminum heatsink I was building into an amplifier. I received MANY 
> plausible and useful replies. I promised a brief summary of the results,
> so here it is!
> 
> In order of frequency of appearance, the suggestions were:
> 
> 1. Use a dremel cutting wheel to cut a slot in the broken tap and 
>    remove it with a flat-head screwdriver
> 2. Beg, borrow or buy ("steal" looks bad!) an appropriately sized tap
>    remover. This device has fingers that slide down into the slots in the
>    sides of the tap. One tightens the grip of these fingers on the tap and
>    slowly works the tap out. George ? mentioned making a device to do this
>    from piano wire,
> 3. Beg, borrow or buy a chemical agent (a name and chemical composition
>    was specified) tradethat dissolves the steel tap while leaving the 
>    aluminum intact. 
> 
> Thanks Again!
> 
> Michael Lloyd

I must have missed this note when it was originally posted.  There is a 
forth possibility: EDM.  EDM stands for (I believe) Electrical Discharge
Machining.

Last year, while putting a steel stud into and aluminum intake manifold, 
I broke the stud off *below the surface* of the aluminum.  For those not
aware, a good 4 barrel intake manifold runs about $150.00.  My wife and I
were not willing to just toss out this manifold with the empty coke cans
for the recycler.

A machinest (sp?) friend of mine suggested that I take it to a Tool & Die
maker here in Boise.  Total cost was $11.00, work was done in 48 hours, 
with no trace of the steel left and no discoloration or marring of the 
aluminum.

This is not an official statement of The Hewlett-Packard Company. No war-
ranty is expressed or implied. The information included herein is not to be
construed as a committment on HP's part. 

"There can be only one!" - Conner McLeod of the clan McLeod
"I will not be pushed, filed, stamped, indexed, briefed, debriefed, or 
numbered - I am not a number, I am a free man!" - Number 6

Kevin C. Hess	 		The Hewlett-Packard Company
Network Printer Division	11311 Chinden Boulevard
Mail Stop 524			Boise, Idaho  83714-0015  USA
hess@hpbs917.boi.hp.com		(208) 323-3384
Newsgroups: rec.audio
From: slee@eng.auburn.edu (Sanguk Lee)
Subject: ADDRESS OF AUDIOPHILE IN ATLANTA !!!!
Reply-To: slee@eng.auburn.edu
Organization: Auburn University Engineering
Date: Fri, 4 Sep 1992 04:56:15 GMT

IF ANY OF YOU KNOW ADDRESS OR PHONE # OF AUDIOPHILE IN ATLANTA
LET ME KNOW IT.

THANX IN ADVANCE

Sanguk LEE
_______________________________________________________________________
Sanguk Lee : 644 W. Magnolia Ave. #A11, Auburn, AL36830, USA
		(205) 826-8358; (205) 844-6806

	Dept. of Aerospace Engineering
	Auburn Univ.
	Auburn, AL36849
_______________________________________________________________________


Newsgroups: rec.audio
From: mather@sees.bangor.ac.uk (Paul Mather)
Subject: How do I clean LPs?
Organization: Centre for Applied Obfuscation.
Keywords: HELP!
Date: Fri, 4 Sep 1992 18:33:16 GMT
X-Posted-From: sol.sees.bangor.ac.uk
X-Posted-Through: sol.ctr.columbia.edu

I just got a 2nd hand copy of Michael Moorcock & The Deep Fix's _The New
Worlds Fair_ LP today.  Sadly, on playing it sounded as if two armies
had camped in each speaker and were enjoying their breakfast crunchy
cereal.

Inspecting the LP, although I don't know for definite whether this is
the case, I suspect that it has been "treated" with anti-static fluid;
it has that characteristic "stickyness" when using a carbon-fibre brush
on it. :-(

Ok, so that's the bad news.  What I want to know is whether or not there's
anything I can do about it?  Can I clean the LP so as to remove this gunk?
If so, will it necessarily make the sound better?

Is it reasonable to assume that anti-static fluid is causing this?  (Like
I said, there is higher resistance when trying to move a carbon-fibre
brush over the surface so, IMHO, this doesn't bode well for the stylus
itself.)  The surface noise is confined almost totally to the extreme
edges of the soundstage, perhaps a tiny bit more so in the right speaker
but not significantly so.

So please folks, is there anything I can do to rejuvenate and rehabilitate
this LP?  As it stands the surface noise is highly distracting.

Any general tips on cleaning LPs are also most welcome.  I'm asking
here because there doesn't appear to be a FAQ for this group.

Cheers,

Paul.

PS: Yeah, I know, "Buy it on CD!"  Trouble is it isn't out on CD.
-- 
e-mail: p.mather@sees.bangor.ac.uk

If your mailer can't reach me, I'm obviously not worth talking to.
Newsgroups: rec.audio
From: timab@dhhalden.no (TIM ALEXANDER BYE)
Subject: New speakers...
Keywords: Criticism.....
Organization: Ostfold College
Date: Mon, 31 Aug 1992 12:04:12 GMT

Is there anybody out there with a objective serious article about the KEF 
Q8? I have just bought a pair and 2 me they sound just GREAT. Any opinions 
on how long time they need 2 get really warmed up?....

anything....
   __/__/__/          __/      __/     "Making love and music is the -
     __/     __/    __/__/ __/__/     only thing worth fighting 4" - Prince
   __/     __/    __/   __/ __/        ! Timab@fenris.dhhalden.no!
 __/     __/    __/       __/          ! TIMAB@sofus.dhhalden.no !
Newsgroups: rec.audio
From: leconte@irisa.fr (Thierry Leconte bureau AB 302 poste 7294)
Newsgroups: rec.audio
Subject: Re: Bi-Amp vs. Bridged Bi-Wire
Date: 2 Sep 92 11:59:49 GMT
Reply-To: leconte@irisa.fr
Organization: IRISA, Rennes, France

In article 9571@jarvis.csri.toronto.edu, smith@eecg.toronto.edu (Michael B. Smith) writes:
>Assume that you have speakers that can be bi-amped and you happen to
>have four amps available.  One possible setup would be to bi-amp the
>speakers (i.e. one amp for the left tweeter, one amp for the left
>woofer, etc.).  Assuming that your amps can be bridged, it should also
>be easy to hook these speakers to be only bi-wired, but driven by
>a bridged amp.  This should provide about double to triple the power,
>so they'll probably be louder.  But, the big question is, which version
>should sound "better"?
>  What are the merits of bi-wiring?

Theorically none .
Bi-amping is more understood. The two amps see a less complex load.

But if you have all these amps why not bi-amping with an active crossover ?
The result will be  surely better.

---
 ___________________
/_______  _______  /        Thierry LECONTE
       / /      / /            BULL/IRISA
      / /      / /         Campus de Beaulieu
     / /      / /_____     35042 RENNES CEDEX
    /_/      /_______/           FRANCE
email : leconte@irisa.fr   telex : 950473 UNIRISA
phone : 99 84 72 94        fax   : 99 38 38 32 
From: pauls@trsvax.tandy.com
Date: 26 Aug 92 10:02 CDT
Newsgroups: rec.audio
Subject: Re: Where can I find the Nyquest theore
Message-ID: <287500048@trsvax>
Nf-ID: #R:fcom.cc.utah.edu:12909:trsvax:287500048:000:319
Nf-From: trsvax.tandy.com!pauls    Aug 26 10:02:00 1992


See Chapter 3 of "Discrete Time Signal Processing" by Oppenheim and
Schafer, Prentice-Hall, ISBN 013216292X. Avail by calling 1-800-922-0579 or
201-767-5937.

This is the updated version of the "Holy Bible" of DSP.

The original paper is "Certain Topics in Telegraph Transmission Theory", in
AIEE Transactions, 1928!!
From: Richard.Chalk@bbs.oit.unc.edu (Richard Chalk)
Newsgroups: rec.audio
Subject: Sony 8MM VCR With PCM Digital Audio
Date: 31 Aug 92 20:14:28 GMT
Distribution: usa
Organization: Extended Bulletin Board Service

Sorry for the public post, but I haven't figured out how to re-read a 
message already read.

Someone was asking about using the Sony 8 MM VCR's PCM Audio for audio
only.  I have both a EVS-800, and an EVS-900, the only difference being
that the 900 is Hi-8 video, and has S-Video (Y/C) connectors.  Neither
one has digital or optical connectors for the audio.  The audio
performance is equal on both machines, and in my opinion is excellent.

I wish to sell the 800 for $400.00 plus shipping. Please e-mail if you
are interested, or call voice at 404-587-1613.  Thanks.
Richard
 


--
   The opinions expressed are not necessarily those of the University of
     North Carolina at Chapel Hill, the Campus Office for Information
        Technology, or the Experimental Bulletin Board Service.
           internet:  bbs.oit.unc.edu or 152.2.22.80
Newsgroups: rec.audio
From: hiroki@AIX (Hiroki Morizono)
Subject: Bose Acoustic Cannon
Reply-To: hiroki@limerick.cbs.umn.edu
Organization: University of Minnesota
Date: Tue, 1 Sep 1992 08:12:52 GMT

I saw one of these in the Toscanini's Ice Cream in the MIT Student Center
and was wondering if anyone out there has tried to make their own--
It's basically a long (10 footish) tube with (presumably) a speaker cone
mounted inside it.
My guess is that it is just a bigger and straighter cousin to the acoustimass
box. Anyone know what the magic ratio for front and back tubes should be?
Someone out there must have taken Bose's class...
Anybody working at Tosci's and reading this group got a ruler?
Hello? Hello?
Also, is there a FAQ for this group somewhere? 

Email preferred if possible,
Thanks 
Hiroki
hiroki@limerick.cbs.umn.edu
From: fontana@iguana.cis.ohio-state.edu (Mark Fontana)
Newsgroups: rec.audio
Subject: Re: An old 8-track cassette player
Date: 30 Aug 92 03:18:45 GMT
Article-I.D.: cis.1992Aug30.031845.23292
Organization: The Ohio State University Dept. of Computer and Info. Science

In article <X1gaqB4w164w@cellar.org> hacksaw@cellar.org (Hacksaw) writes:

>I have an old 8-track audio cassette player and I was wondering if there was 
>a "converter" or something in which I could put a standard audio cassette 
>into and have it play. For example, there are VHS tapes that allow you to 
>play an 8mm film.

8mm film?  I doubt it!  :)  8mm video?  Possibly, but the only ones I've
seen were for VHS-C.

>Is there a 8-track tape that allows me to insert a regular 
>tape into it? Thanx in advance.

  Yes, these devices exist (or once existed :).  I think my parents
used to have one made by Radio Shack that they used to play tapes in
their old car.  It stuck in like a cartridge and had a big ugly
box protruding from the 8-track player.

My question to you is- WHY?!?


Mark
From: sss@castle.ed.ac.uk (S S Sturrock)
Newsgroups: rec.audio
Subject: Re: Sony Mini-Disc Questions/Debate
Date: 26 Aug 92 10:32:31 GMT
Organization: Edinburgh University

In article <1992Aug25.213444.5225@fid.morgan.com> sethb@fid.morgan.com (Seth Breidbart) writes:
>In article <MARC.92Aug21091602@mamba.es.ele.tue.nl> marc@es.ele.tue.nl
>(Marc Heijligers) writes:
>>
>>In article <24809@castle.ed.ac.uk> sss@castle.ed.ac.uk (S S Sturrock) writes:

I just want to say that none of the stuff you were arguing with was by me,
it was Marc, I don't want some of his statements attributed to me.

>>*you* hear.
>
>Or what you don't hear.

Here I agree with Seth, so much emphasis is placed on what we can and can't
hear these days, this is a very dangerous situation.

Shane


-- 
Shane Sturrock, Biocomputing Research Unit, Darwin Building, Mayfield Road,
University of Edinburgh, Scotland, Commonwealth of Independant Kingdoms.  :-)

Civilisation is a Haggis Supper with salt and sauce and a bottle of Irn Bru.
Newsgroups: rec.audio
From: carlwu@magnus.acs.ohio-state.edu (Carleton Wu)
Subject: Re: HSU Research Sub woofers
Keywords: woofers
Organization: The Ohio State University
Date: Sat, 29 Aug 1992 20:46:58 GMT

In article <183295@pyramid.pyramid.com> lstowell@pyrnova.pyramid.com (Lon Stowe
ll) writes:
>    By the time you buy the HSU's and amplifiers, you have spent as
>    much as the lower end Velodyne or M&K...either of which will
>    rattle the walls better.   This is not to bad-rap the HSU's.
>    They sound "ok", but nowhere near the powered models I've heard.
I beg to differ.  The Hsu's can wallup over 100dB with just 50W of power.
Remember, two subwoofers have a 6dB advantage over the single unit you speak of
so fondly and with such blatant bias.  Furthermore, I'd be interested to know
where you auditioned the Hsu's (available ONLY factory-direct) and the others.
And under what circumstances.  I'm sure your local M&K dealer is more than
willing to boost the bass region to demonstrate their products instead of a
flat response.

>    If you want killer sound, buy two Velodynes or M&K's and put
>    them in different room locations to help with standing waves.
Or just one set of Hsu's. :-)

>    I'd avoid the cheapest Velodyne and M&K models, they only have
>    about 50-60 watts and only are flat down to 30 Hz or so....but
>    either make has higher end models that are flat to 20, and some
>    down to 15-18 at room-shattering levels.
I really don't get it.  First you imply that low-end Velodyne/M&K's are
preferable to the Hsu's in sound and comparable in cost when you tally in the
extra amp for the Hsu's, and now you're saying that they are ONLY flat to
30Hz!  The Hsu SW10 subwoofers reach down to 20Hz!  Even the inexpensive dbx 
subs could probably reach 30Hz.

I have had my Hsu SW10 subwoofers for about a 3 weeks now and am very satisfied
especially considering the cost.  Don't know how much the Velodynes or M&K's
cost, but with the extra amp, the total came to $920, including S/H.  The only
thing I don't like about them are the "spikes" they came with them which are
really only screws you twist into the bottom (SR conveniently left this cheap
point out of their picture of the subs)--not exactly very sturdy.
I would write a product review on 'em but I haven't had much time to listen to 
music lately, with school starting and all.

In the future, if any of you are going to make product comparisons, please be
fair about it.  Preconceived bias can only serve to skew the outcome.

Carleton Wu
Newsgroups: rec.audio
From: aj008@cleveland.Freenet.Edu (Aaron M. Barnes)
Subject: Re:Sony 696HF VCR's for $329!
Organization: Case Western Reserve University, Cleveland, Ohio, (USA)
Date: Sat, 29 Aug 92 17:17:36 GMT


The purpose of this posting is to apoligise to the net for not be
ing of much help.
A few days ago,I asked if anybody knew where to get the said VCR 
for the lowest price possible.
A gentleman sent mail stating he knew where to get them for $329.
He then told me he would not reveal the dealer because I didnt ask
nice enough,or something like that.
So,I proceded to post his address so everyone on the net could ge
t in on the savings.I did not know that was against the rules,and 
for that I apologise to him.
But when he posted saying my posting was a prank-NOT TRUE.
I have his mail to me to back up my claim-he only has his word.
So,dont be upset with me,he wont release the information-I attempe
d to save the net some money.

He also seems to think I was harrasing hiim.
The only way I can answer that is-if I was trying to harras him,he
would have known about it.My intentions were not to harras him.

So,I am sorry for not getting the information out to the net.

I leared something through this experiance-dont post other people's
addresses,and-not all people are as nice as yourself.

Thanks.
-- 
Aaron Barnes
aj008@cleveland.freenet.edu
Part 15 will take over broadcasting one frequency at a time!
Howard Phillips for President!
From: oconnell@vms.macc.wisc.edu (Kevin Patrick O'Connell)
Newsgroups: rec.audio
Subject: 3-D Acoustics speaker repair--did I get ripped off?
Date: 24 Aug 92 00:21:27 GMT
Organization: University of Wisconsin Academic Computing Center

Ok, here's the deal:

A friend gave me a set of 3-D Acoustics speakers, 2 satellites and a 
central sub-woofer thang.  The satellites sustained some damage in a 
fall:  the woofer cones were torn somewhat from their mountings (the
particle board around the screws failed, and the woofers were 
dislodged).  This Guy At The Stereo Repair (Paragon, for those kind 
readers in Madison) sez that the cones are "slightly dented" and that
after some use, the voice coils will begin to touch the thing that 
surrounds them, in effect shorting the circuit and frying my HK380 
amp/receiver.  (Now, I know that they played in this state, since I
hooked 'em up anyways before I went to see the GATSR, and music came
out all 3 units).  

The GATSR sez to replace the cones, and recommended cones made by a 
Danish firm called Jamo (6 in. woofers, model # w20369), for $60 the
pair, $84.40 with labor and tax.  (One crossover needed some attention
as well, but no extra parts).  

So--wuz I robbed?  I thought that $60/pr seemed pretty cheap for 2 
hi-tech cones, and especially so since the ones that suffered the 
damage seemed more complex in construction.  Alas, I know zip about 
what makes a good driver/cone, so I basically gave him the go-ahead.
(Sorry, I can't give the model of the 3-D acoustics, because there
was no obvious one on the cones/drivers, and there was none on the 
cabinets.)  They are about 7 yrs old, I guess.  GATSR said that they 
listed about $400-500 new, but I wonder if he was BS'ing . . . .

Any ideas?  Thanks for your time!

Kev 
Organization: Sophomore, English, Carnegie Mellon, Pittsburgh, PA
Newsgroups: rec.audio
Date: Sat, 29 Aug 1992 11:49:31 -0400 
From: Eugene Kuo <ek1i+@andrew.cmu.edu>
Subject: Pulse Technology

I just recently bought a Sony DCP-C315, and it states that it uses the
Pulse Technology.  What IS it?  Any info would be welcome.  And I'm
sorry if this has come up before.  Thanks in advance!

        eugene
From: andrew@alice.att.com (Andrew Hume)
Newsgroups: rec.audio
Subject: Re: speakers: NHT vs. Energy ?
Summary: say what?
Date: 29 Aug 92 16:58:35 GMT
Article-I.D.: alice.23589
Organization: AT&T Bell Laboratories, Murray Hill NJ



	your tastes may different than mine but when i recently heard the NHT's,
i thought them poor speakers. in fact, the expensive model (1.8's i think)
that costs around $900 was easily poorer than the $500 PSB 500 and the
$450 Fried Q/4 and so vastly outperformed by the $990 Snell E/III that
wasn't funny. The $650 Snell J/III [not too sure of this model number]
is also worth looking into; its much like the E/III but not as good.

	andrew hume
From: myers@hpfcso.FC.HP.COM (Bob Myers)
Date: Wed, 26 Aug 1992 15:56:15 GMT
Subject: Re: DAT vs Analogue (was Who dat say dey gonna buy dat DAT?)
Organization: Hewlett-Packard, Fort Collins, CO, USA
Newsgroups: rec.audio

>A cheapo $600 DAT deck outperforming $2000 analogue decks?  har har har!
>Leave those scopes alone and listen to the damn thing!  The *APPALLING* ADC
>set ups in consumer DAT decks with their magnificent pre-sampling filters
>are just a joy to behold.  Har har har!!!!  Not to mention the things being
>full to the brim with poxy op-amps giving cheaps**t Japanese sound.
>
>Sheesh, do you people only listen to bass?  Are your ears so damaged by
>years of excessive volume listening that you cannot hear the detail you are
>missing?  The life?

This is rich!  The digiphobes' standard wail is for those espousing digital
audio to "stop using the specs and use your ears!" - and then when someone
DOES use their ears, and still prefers the digital recording (going against
their Most Holy Biases), they can do nothing more than attempt to insult that
person's ability to hear.

Never ONCE does anyone, even for a moment, concede that their preference for
analog just MIGHT be only that - their personal preference - and that other
people could legitimately have differing views.  A pity.



Bob Myers            | "One man's theology is another man's belly laugh." 
myers@fc.hp.com      |                     - Lazarus Long/Robert A. Heinlein
                     |                                
Newsgroups: rec.audio
From: Janne.Anttila@lut.fi (Janne Anttila)
Subject: Re: How do I use a "bias fine adjustment?"
Date: Wed, 26 Aug 1992 15:01:48 GMT
Disclaimer: Graecum est, non legitur.
Organization: Lappeenranta University of Technology, Finland

In article <1381@eouk9.eoe.co.uk> ahaley@eoe.co.uk (Andrew Haley) writes:

   The recording level doesn't matter that much for bias setting.  Use a
   realistic level, and choose the setting that sounds most like the
   source.

   Andrew.

Actually the level does matter, since many decks can't reproduce
the highest treble at higher recording levels. Even if the frequency
response of the deck goes up to 20 kHz at -20 dB, it might only reach
9 kHz at 0 dB, especially with normal type tapes. If you record pink 
noise at 0 dB and try to correct too little treble by reducing bias, 
you will probably get peculiar results.

I usually do the bias setting at -20 dB.

 
--
	Spirits make me move in mysterious ways...
						   Janne Anttila
-- 
	Spirits make me move in mysterious ways...
From: YKWON@SLACVM.SLAC.STANFORD.EDU (415)
Newsgroups: rec.audio
Subject: cd player
Date: 31 Aug 92 22:27:34 GMT
Organization: Stanford Linear Accelerator Center

I am in the hunt for a good single-play CD player with moderate price.
Does anyone have an opinion on
        ADCOM GCD 575,
        Carver SD/A 490t
        Rotel 965, 955
or any other models comparable to these?

Sound quality is the most important but the mechanical stability is also
very important to me.

Thank you.
Newsgroups: rec.audio