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Music servers and other computer based digital audio technologies.

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RE: 'IMO, SPDIF from a computer would be the last method of connectivity to use as far as digital connections.

Posted by audioengr on March 19, 2008 at 23:14:25:
I read the test results on these de-jittering devices. Not very good results IMO. It seems to me that the test set-up must have had a fairly bad ground-loop of some kind as all of the wired results were actually worse than the original jitter. Only the Toslinks seemed better.
The Theta TLC evidently has a transformer coupling the S/PDIF output, but like many manufacturers, it is wired as an auto-transformer which eliminates the galvanic isolation. It sounds a lot like the DDDAC which uses a free-running oscillator and an 8412 or 8414. The way this works is that as it "precesses", it throws away samples from the input stream to avoid sync problems. Not bit-perfect, but one way to sync the stream to an asynchronous clock.
These results are actually not so great - 0.5 nsec to 1 nsec of jitter. The risetimes of some of these are 2-3 nsec, so the jitter should not be this high. Probably a result of using inexpensive oscillators, or at least not the best choices IMO.
Steve N.