I concur most heartily with Tom Fine's remarks. While much is known, much
yet is to be discovered -- or brought into production. The real error in
RBCD is our thinking that it works exactly as the (frequently appended)
textbooks tell us.
Which brings me to:
"Is anyone suggesting that fluctuation in the rotating of the disc itself
can have ANY effect on playback? Do I misunderstand something? Since the
data stream is buffered the speed with which it is read from the disc cannot
possibly have any effect on the playback speed which is controlled by the
DAC clock. So what is the above quote intended to convey?"
It is being suggested that all manner of things affect playback. Speaking as
an ex-digital designer (albeit optical) on the Mars Lander Camera, the error
budget for RBCD has not yet been written nor all the contributors identified
-- de rigueur for any NASA project but CD has never been systematically
analyzed. Hence it should not be surprising that improvements can be
discovered. I'll offer a couple of my own: vibration isolation and surface
cleaning/polishing. Yet it is widely supposed that players are robust enough
to overcome such difficulties; they are not.
On Fri, Nov 19, 2010 at 10:27 AM, Alex Hartov <
[log in to unmask]> wrote:
> Hi Folks
> Sometimes I have to express serious doubts about what I read. From the
> given URL I read the following:
> "Many years ago, an irate musician contacted his CD-DA replicator claiming
> that his latest release was of poor quality. Extensive electrical,
> mechanical, and listening tests by the replicator failed to disclose any
> flaws while the musician became angrier. The persistent replicator finally
> identified a defective glass mastering turntable in which one coil of its
> brushless DC motor had failed, causing an imperceptable once- around speed
> variation. After repair, the musician declared his satisfaction in the
> resulting high CD-DA quality."
> Is anyone suggesting that fluctuation in the rotating of the disc itself
> can have ANY effect on playback? Do I misunderstand something? Since the
> data stream is buffered the speed with which it is read from the disc cannot
> possibly have any effect on the playback speed which is controlled by the
> DAC clock. So what is the above quote intended to convey?
> Alex Hartov
> On Nov 19, 2010, at 9:30 AM, Rob Poretti wrote:
> > -----Original Message-----
> > From: Association for Recorded Sound Discussion List
> > [mailto:[log in to unmask]] On Behalf Of Jerry Hartke
> > Sent: November 18, 2010 8:10 PM
> > To: [log in to unmask]
> > Subject: [ARSCLIST] Listening Tests
> > Input on the subject has been posted at:
> > www.mscience.com/faq35.html
> > Jerry
> > Media Sciences, Inc.