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How to improve Jitter issue via USB/ETHERNET ?
#40
(02-Apr-2018, 15:04)thumb5 Wrote:
(02-Apr-2018, 14:22)yabaVR Wrote:
(01-Apr-2018, 11:28)K4680 Wrote: Hi, worth knowing about jitter etc! Rolleyes
http://www.jitter.de/english/engc_navfr.html

Thanx for the link. These pages should be read by everyone who wants to contribute to any thread in 'Streaming' and 'Tweaker's Corner'. A lot of questions are answered there...e.g. why USB-cabels all sound different (and more).

gui

Perhaps predictably, I beg to differ.  The article is interesting but as far as I can see it talks specifically about clock jitter in S-P/DIF and Toslink, where the audio sample clock has to be recovered from the input signal.  It is misleading to think it's directly relevant to USB and Ethernet, because these protocols are clocked completely asynchronously to the audio samples; the samples are not expected to arrive at intervals of the audio sample period.  The concept of clock or inter-sample jitter doesn't make any sense - it's simply not defined - for samples delivered asynchronously like this.  In fact you get bunches of samples all at once at more or less predictable times (more predictable on USB, less so on Ethernet), and it's up to a higher-level agreement between the sender and receiver what the time period between individual samples is supposed to be.  The receiver then has to generate an independent clock at the agreed rate to play the samples; that clock will have some degree of jitter, but in any reasonably-designed system that should be completely independent of the USB or Ethernet clock.  There could be jitter in the USB or Ethernet clock, of course, but either that results in packet errors - usually meaning drop-outs - or it has no effect on higher layers.

This is a assumption on your side.
In theory everything is clear as day but if you compare two different brands of USB cables (each of the same length e.g. 1m) you get two different results in sound.
I even don't say one has to better than the other (well...it has to be...otherwise there's no difference) but you can clearly distinguish sound differences in one over the other (how to weight them is to you). This differences to a large degree comes from cable induced jitter (ok, this is my opinion but in common with many others). By your theory it should have no effect but even similar designed USB-cables sound different and it is the same with Ethernet-cables (at least my experience over many years in the business).
Now...can you fool someone/yourself in an AB session. Sure you can and even in an ABX session. There's no perfection. But it is most unlikely you are fooled or fool yourself within 30 years again and again.
If my experience is confirmed on every new occasion I don't care about old written theory...I'd care about new theories that explain what I'm experiencing...I want to know.

gui
"Oh, you can buy the other. But then it is a cost intensive learning process"
berlin
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RE: Devialet has NO Jitter issue via USB/ETHERNET ? - by yabaVR - 02-Apr-2018, 16:09

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