|Jitter is a matter for the DAC (assuming it reclocks) correct? Since this stage involves analog signals, I was not refering to this stage, but rather just the transport. But if you're saying that all (higher end) transports read CDs/DVDs with near 100% accuracy, and is only the DAC that ultimately affects the sound, then I guess I am misinformed about the situation, and retract my statement.
Well, the master clock is set by the transport when it reads the data, and everything downstream is based on that clock. Good DACs will clean up the clock signal with advanced PLL's, and some people are developing DACs that completely recock the incomming data, but those are very rare. (i'm not even sure if there are any commercially available) For most DACs, jitter in the transport will make its way to the output.
This is the reason that people claim transports and even digital cables affect sound quality, though i agree that its much better to deal with it in the DAC design rather than spend $$$ to ensure everything before it is perfect.
|: Is that also for audio cds? I know computers use a sort of correction where it sees the data, and if its incomplete, tries to complete it.
All Cd's have the basic error correction; there is lots of redundant data written in that will correct a certain number of read errors. A mathematical formula uses this extra redundent information to fill in missing data, up to a certain point. I believe its somewhere around 140 errors per second, but its been a while since i've looked at this stuff. Anything below that will be corrected to 100% accuracy, once you go above that, different transports will do different things-i believe some will round it off, others will simply drop the sample.
Data CD's have additional layers of error correction. In fact, i think almost half of the capacity of a CD is used just for error correction with data. Again, they use complex mathematical algorithims and the extra redundant data to correct errors. Data CD's definately don't guess data (if it encounters too many errors, it'll give you an error message) , while audio likely will try and guess the damaged data...