"Scott" wrote in message
they were not current for sure. These tests were done in
service of the production of his 1994 remasters of the
Mercury classical catalog. This particular anomly was
discovered when he was testing the physical product from
various manufacturers. He discovered that with certain
CDPs the CDs from some manufaturers were quite less than
transparent compared to the masters. This observation was
later confirmed in a number of other tests conducted by
other parties.
There is an extant AES paper that was presented by Dennis Drake in 1992
presented in its entirety at this URL:
http://www.themusiclab.net/aespaper.pdf
It says:
"As Mrs. Cozart Fine and I began our evaluation sessions in April 1989, it
became
very clear to us that the A/D conversion process was a very critical step in
our production
work. As the producer once described it, the sounds from different
converters were
all different "bowls of soup". We began auditioning every A/D converter that
we could
obtain. Our test methodology was simple: while playing an original master as
source, we
would switch between the direct output of our console and the output of the
digital
chain. The digital chain consisted of the converter under test feeding a
Sony 1630 PCM
Processor. The final link in the chain was the Apogee filter modified D/A
section of the
Sony 1630. At times, we would substitute different D/A converters for
listening evaluations,
but we always returned to the Sony converters or the D/A's of our Panasonic
3500
DAT machine for reference purposes.
"Our monitoring set-up consisted of a Cello Audio Suite feeding balanced
lines to
Cello Performance Amplifiers, which in turn were driving B & W 808 Monitor
Loudspeakers. As we compared the various digital converters to the playback
of the
actual analog source, we found that the soundstage of the orchestra was
always
reduced in width when listening to the digital chain. We also found that
many A/D converters
exhibited a strident string sound, unnatural sounding midrange, and a loss
of air
or ambience around the instruments"
This above formal presentation of the relevant so-called Denni Drake tests
includes many details that are different from what we have seen presented on
RAHE. For one thing, the evaluation was not of CD players, and for another,
there is no evidence of level matching, time synching, or bias controls.