DVD-Consortium vs. SONY/Philips or...

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The burning speed may influence jitter. Bob Katz wrote in a letter on his site www.digido.com:
“...A large group of mastering engineers and critical listeners agree that CDs cut in different ways tend to sound different. The CD differs from other storage media in many ways, but the critical point is that the timing of the output clock and the speed of the spinning disc are related. The output of the CD player is a clocked interface, and the data are clocked off the CD disc in a ‘linear’ fashion, one block of data after another. A buffer is used, which theoretically cleans up the timing to make it regular again, and, for the most part, it does.

“A lot of this is theory...no one has proved it as fact. And there may be more than one mechanism causing jitter taking place.

“To obtain jitter in the low picosecond region requires extremely accurate timing. Any leakage current (interference) between the servo mechanism controlling the speed of the spinning disc and the crystal oscillator controlling the output of the buffer may destabilize the crystal oscillator enough to add jitter to the clock signal. This does not change the data, by the way. If the servo is working harder to deal with a disc that has irregularly spaced pits or pits that are not clean, perhaps leakage from the servo power affects the crystal oscillator. It doesn’t take much interference to alter a clock by a tiny amount.

“This jitter is ‘ephemeral,’ though, because you can copy this data (irrelevant to the clock) and then play it back again from a more steady medium...and make it sound ‘good’ again. This is not a permanent problem.”



I think every disc burner has a certain speed where irregularity is minimized, but I don’t know how to prove it.
– adebar, Wiesbaden, Germany
 

TNT

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"The output of the CD player is a clocked interface, and the data are clocked off the CD disc ....."

lets look at this statement:

and the data are clocked off the CD

that clock has absolutley nothing to do with what You hear from a cd player - I assure you !

the quotes in Your post, are they taken out of context or? They talk about cd players - timing - clock - jitter ??????

You stated "There are jitter problems in pure digital transfers." but Your last post is about "output from a CD player" ;-)

/
 
And furthermore, even if the positional jitter on the CD may be
able to affect the clock jitter of the DA conversion, this is still
a problem that lies entirely within the CDP. If the CDP is sensitive
in that way, the quality of the CD burner/CD pressing plant may
matter. However, jitter in ripping a CD and jitter in hard disk
data still has no effect whatsoever on this, as BritishSpy seem to
have claimed earlier.
 
phase_accurate said:


:D :D :D

I still wonder why no one so far offered the completely noise- and distortion- free CD player that has it's outputs shorted from the beginning.
This would indeed be a big aural improvement with some CDs. :devilr: :devilr: :devilr:

Regards

Charles

At least it's a simple tweak, and you can even put in a switch
so you can choose for each CD you play whether to use the
tweak or not. Better still, avoid buying those CDs in the first
place. :)
 
I have this switch already factory installed (I had it on all my cd players), reduces also all jitter to an absolute minimun, and it switches the display off automatically.
The only setback to this switch is that the open button for the loading mechanism doesnt work when this switch is activated.
 
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