Mark,

You still do not get it.

You write:
Which device reads a CD most accurately?
Which device delivers that data most accurately?

In the analogue world we needed to think in terms of “most accurate”. No system was completely accurate. As you got closer to accurate, there was room to talk about the flavor and aroma of the sound.

Digital is a whole new world, you have the bits that were written on disc. Either they get to the speaker or they don`t. They are accurately transmitted or they are not. If you use fancy gold etched wire that is blasted with gamma rays while frozen, you still have the same bits or errors. Any bit that is different from the original is considered an error.

If your CD drive is not reading the bits properly off the disc you need to buy a new CD drive. It is a terrible thing to say but a cheap drive from Wal-Mart will read the same bits as the one in a fancy NY showroom. I worked at a large software company for many years, I wrote code for applications that would read data from a CD, we decompressed just about every byte stream that came off a CD. If we ever found an error we would have to abort the application, only perfection would do. Even your cheapest Wal-Mart computer will get the bits off correctly. Ten years ago this was not a big problem and it certainly is not a very common problem today. And you can test this at home, rip a disc a few times, compare the files with windiff.exe. They will be the same every time, hook your compute up to your stereo, even with “PC power supply induced nastiness and conductive noise through the interconnects” the files will still be the same.

As far as this garbage about jitter, every digital signal has jitter. Every USB, Ethernet, Firewire, HDMI signal. Every signal inside the CPU has jitter, the signal to memory has jitter. As long as the jitter is within the tolerance, all of the bits get transmitted perfectly. The tolerance for Jitter is a very small when you are talking about the HyperTransport between CPU proccesors at 24.0GB/s. It is rarely a problem for digital audio. Here again, if the bits are getting across then reducing jitter make no difference. And just to clarify, jitter is not cumulative.

There are many challenges with digital audio, there are firmware upgrades to deal with, re-sampling within the OS, drivers compatablity, ect.. There are plenty of things to fiddle with, but we do not need to worry about “physically decoupled and so transmits no noise”.