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Path: utzoo!watmath!watnot!watdcsu!herbie
From: herbie@watdcsu.UUCP (Herb Chong [DCS])
Newsgroups: net.audio
Subject: Re: A-B-C CD -- Pyromania 2.0
Message-ID: <1369@watdcsu.UUCP>
Date: Sat, 11-May-85 01:04:23 EDT
Article-I.D.: watdcsu.1369
Posted: Sat May 11 01:04:23 1985
Date-Received: Sat, 11-May-85 04:35:19 EDT
References: <970@ulysses.UUCP>
Reply-To: herbie@watdcsu.UUCP (Herb Chong [DCS])
Organization: U of Waterloo
Lines: 71
Summary: 

In article <970@ulysses.UUCP> smb@ulysses.UUCP (Steven Bellovin) writes:

....details of testing and results deleted....

>We invite others to conduct similar tests on their own.
>If you do, we cannot overemphasize the importance of level matching
>(with a voltmeter!) and synchronization.

for others doing this test, the voltmeter must have adequate and known
frequency response.  the critical 1 kHz test tone should be well within
the voltmeter's bandwidth and the two players adjusted to within 0.1 and
preferably 0.05 dB.  if possible, electronic switching should be used
with a HIGH quality relay circuit.

>Other observations:  (a) such differences as were noticed were quite
>small in magnitude; to smb's thinking at least, neither player could be
>called "better" or "worse".  They would be dwarfed by the difference
>between any sets of good speakers.  (b) the strength of the psychological
>desire to hear *something* cannot be overstated.  Given how noticeable
>the switching transient was, it would be very easy to imagine differences
>when none were actually present.  (By comparison, the switching
>transient last time was far less noticeable.  This may be because the
>Heath preamp used has a mechanical switch, whereas the Carver Receiver
>has an electronic switch.) (c) the differences in the human factors of
>the different players was far greater than any sonic difference; even
>if you can hear the difference when listening at your peak, you would
>do well to give greater weight to the controls.  (d) it *is* possible to
>destroy a CD via relatively small scratches...  (*sigh*)

most of these results are well known in psychoacoustics papers by
various people.  a big influence on whether a difference is heard or
not is the expectations of the listener.  the more paid for the piece
of equipment, the greater the desire to hear superiorities, imagined or
not.  frankly, i expect that about the only audible difference that is
significant between CD players is minor variations in frequency
response.  this is not to say that there are a lot of theoretical
advantages to oversampling, but to say that one technique is audibly
better than another when both are so good is not very important.

>               --Steve Bellovin 
>                 Andy Koenig 
>                 Lynda Feng 
>                 Dick Grantges
>                 Jim Johnston 
>                 Phil Karn
>                 Marty Shannon

another test with a bona fide high end, cost-no-object system under
double blind and controlled conditions and known "golden ears" would
help further these conclusions.  AudioScene Canada conducted such a
test about three years back to see whether there was a difference
between MC and MM cartridges.  several highly respected cartridges of
each type selected by the underground audiophile community were tested
with specially selected electronics and equipment under very tightly
controlled conditions.  the NRC audio research studios were used for
the comparison.  many Toronto and Ottawa area "golden ears" were
invited and did these tests individually and as a group.  no discussion
or conversation of any kind was allowed until the tests were complete.
the results were "ego shattering" as one of the testee's said later.
out of the panel of 17 (or was it 16?), only one could distinguish
between any MM and any MC cartridge in a consistent manner.  if people
are interested, i can post more detailed results and the summary.

Herb Chong...

I'm user-friendly -- I don't byte, I nybble....

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