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I am skeptical about polishing CD's beyond a non-defective finish from the factory. I'm not at all 
skeptical about stable mechanical transport. I would suggest that regarding the polishing, science 
needs to be done as to measured error rates before and after polishing. I can't think of what else 
polishing would effect, it shouldn't effect mechanical jitter. One thing I notice -- there doesn't 
seem to be too much controversy anymore that a careful listener can hear jitter artifacts, but there 
seems to be much controversy about whether one can hear correction of correctable read-errors.

-- Tom Fine

----- Original Message ----- 
From: "Clark Johnsen" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Friday, November 19, 2010 11:16 AM
Subject: Re: [ARSCLIST] Listening Tests


>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.
>
> clark
>
> 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.
>>
>