cliveb;145869 Wrote: 
> Every CD player, since the year dot (ok, 1983, when CD players were
> introduced) has done precisely this. The data coming off the spinning
> disc is decoded and placed into a small buffer, from where it is
> clocked out by the master clock at the CD player's DAC. You don't need
> megabytes of buffering to do this, because the DAC's clock is also used
> to modulate the rate at which the disc is read.

So the speed of the transport motor is constantly changing to keep the
small buffer at an appropriate level?  Seems like there is a very small
margin for error in this approach.  If your statement is true, why do CD
players of similar componentry to the SB3 sound so much worse?

cliveb;145869 Wrote: 
> And I'm a little surprised by Sean's statement about how data should be
> distributed around the disc so that if a small area of the disc is
> obliterated the data can still be recovered, because this is exactly
> what is done on CDs, to a certain extent. Perhaps Sean was suggesting
> that the way it's done doesn't go far enough, but the way I read his
> post it seemed to imply it wasn't done at all.

As I understand it, the error correction for Red Book audio is
distributed, but only nearby, and is nowhere near the quality of ECC
data level error correction in Yellow Book CD-ROM data discs.  I think
Sean is suggesting that the disc be treated as a data disc rather than
a real-time delivery mechanism.  Then you can go to another part of the
disc to pick up error correction information, fix the errors, and go
back filling the buffer with data.  But this only works if you have a
big buffer that can handle the buffer draining while the error
correction takes place, and can then handle re-filling the buffer at
high speed by running the disc at multiple times the data consumption
rate.


-- 
pvadbx
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