wjm@whuxk.UUCP (08/01/83)
As I was reading the August "Audio" reviews of the CD players, I was somewhat
concerned (to put it mildly) about the the ringing on the 1kHz square wave
response pointed out by Kim Rochat. I am also concerned about the effects
of the phase shifts pointed out by Rochat. Today, we routinely expect BETTER
transient response from analog components, such as phono cartridges and amps
and this may account for the sonic problems of some early CD's. Given that
much music (piano, percussion, etc) consists of transients, what does this
ringing do to the music? I would doubt that all CD players would sound
identical (given the variations in sampling algorithms and error-correction
systems I've read about in "Audio" and "Stereo Review"), and one important task
facing the audiophile community in the immediate future is to determine which
tests separate the "sheep from the goats" among CD players by determining which
ones are audibly superior. I suspect that transient response (as determined by
the 1 kHz square wave test) may very well be significant. As for phase shift,
there is considerable controversy about its audible effects (as one can see when
reading ads for high end speakers). Personally, I think I'll hold off buying
a CD player until 1) more CD's become available
and 2) the next generation of CD players without some of the
audible bugs of the present batch become available.
Bill Mitchell
(whuxk!wjm)
Disclaimer, the opinions expressed here are my personal ones, and do not
necessarily reflect those of my employer, Bell Laboratories.