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Old 16th Oct 2017, 2:14 pm   #207
G8HQP Dave
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Join Date: Sep 2008
Location: Solihull, West Midlands, UK.
Posts: 4,872
Default Re: Audiophoolery. 'Cable Break In' - I never knew that!

Quote:
Originally Posted by cmjones01
All the right bits, necessarily in the right order, but with timing jitter. That's analogue, and measurable, and has a mathematically demonstrable effect on the audio output - a sort of phase modulation, effectively. It'a also an issue for self-clocking digital audio interfaces like SPDIF, either electrical or optical. Of course, buffering the data and re-clocking it from a low-jitter source fixes the problem, but very few DACs bother with that.
Timing jitter comes from clocks (inside CD players) and cables (to external DACs). The optical drive should not affect this, unless the CD player has quite bad PSU and power distribution design. Buffering and reclocking is an inherent aspect of the data de-interleaving and error correction. Hence what goes to the DAC is locked to a crystal clock. High frequency jitter can be added by external SPDIF connections, but the DAC will then include a PLL to remove this.

Jitter can be a problem, but it is not as big a problem as some people fear. Strangely, the popular 'fix' (a bolted-on oscillator 'upgrade') will often make things worse due to interfacing problems such as ground-bounce.
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