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Does a jittery stream affect quality if reclocked?

onlyoneme

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But it can only work effectively if #2 properly works. Clearly in your case, it does not.
It's not about being effective. It's about being possible. And about how the related jitter will affect the stream before the reclocking, as shown on my examples.
 

voodooless

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It's not about being effective. It's about being possible. And about how the related jitter will affect the stream before the reclocking, as shown on my examples.
But that’s contrary to what ChatGPT said…
 

pkane

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What do you think is this then?

View attachment 281639

Would you retrieve the same bits from the spdif carrier when there are different source devices with different clocks and your receiver doesn't lock to the incoming spdif clock?

I'm struggling to follow this discussion, but the difference between these two tests (red and blue) appears to be that the red signal was captured in 16 bits and blue in 24. It's not a difference in 'jitter' or lost PLL lock or whatever else is being claimed.
 

voodooless

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Here?
"By using an ASRC, the device can effectively mitigate the effects of clock-related issues, such as jitter or other timing inaccuracies, in the input signal."
Yes, and your example is this process failing…
the difference between these two tests (red and blue) appears to be that the red signal was captured in 16 bits and blue in 24.
How do you reach that conclusion?
 

onlyoneme

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I'm struggling to follow this discussion, but the difference between these two tests (red and blue) appears to be that the red signal was captured in 16 bits and blue in 24. It's not a difference in 'jitter' or lost PLL lock or whatever else is being claimed.
No, the same 48/24 signal all the time and the capture conditions.
 

Achim1812

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For me this infamous "jitter" is about beeing important and creating wishes/money.
Sorry for that, but any up-to-date hifi gear will handle it in a way to avoid listening pain.
 
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voodooless

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Having seen plenty of 16 bit vs 24 bit J-Test results, it's pretty obvious :) What you see with red is the quantization error, not jitter.
This looks similar though:
1682599579227.png

Ah, the frequency scale is quite different, though. Should the 16 bit version not have a much higher noise floor?

@onlyone: what streamers are these, and how did you “feed them”?
 
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onlyoneme

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Sorry, but you had a conversion to 16 bit somewhere during the red capture. This is not jitter, it's quantization error.
What would you say about this one?

1682599851408.png


or this one?

1682600087393.png


"Red" and "green" device.
 
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onlyoneme

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@onlyone: what streamers are these, and how did you “feed them”?
WiiMs Mini and Pro, SMSL PO100 Pro. REW 24 bit dithered signals, played over UPnP for WiiMs and over wasapi for SMSL. All of them perfectly transparent when using clock locking/syncing device without reclocking.
 

pkane

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This looks similar though:
View attachment 281805
Ah, the frequency scale is quite different, though. Should the 16 bit version not have a much higher noise floor?

@onlyone: what streamers are these, and how did you “feed them”?

Here's what quantization error with J-Test at 16 bits:
1682600585343.png
 

bennetng

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What do you think is this then?

View attachment 281639

Would you retrieve the same bits from the spdif carrier when there are different source devices with different clocks and your receiver doesn't lock to the incoming spdif clock?
Looks similar to what I've seen from datasheets of some ASRC chips.
Image2.png
 

RayDunzl

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A little footnote from ESS on the sound of jitter:

Technical Details of the Sabre Audio DAC
Martin Mallinson and Dustin Forman, ESS Technology Technical Staff

https://6moons.com/audioreviews/wyred4/sabre.pdf -- footnote 15

(original ESS Company link no longer works - this one does )

"The noise that jitter induces is not easily described: it is not a harmonic distortion
but is a noise near the tone of the music that varies with the music: it is a noise that
surrounds each frequency present in the audio signal and is proportional to it.
Jitter noise is therefore subtle and will not be heard in the silence between audio
programs. Experienced listeners will perceive it as a lack of clarity in the sound
field or as a faint noise that accompanies the otherwise well defined quieter
elements of the audio program."

--

My thoughts on jitter:

Jitter means the sample is sampled "early or late" at initial digitization, or is decoded into the analog waveform "early or late". What happens in between, as long as the sample data is intact, shouldn't matter.

At the ADC, when the analog signal is digitized, the ADC clock can introduce jitter into the data itself. The sample is taken too early or too late compared to a "perfect" clock. The ADC sampled the wrong point in time on the waveform. Now, "jitter" is in the samples, the sample value is too high or too low, and can't be corrected (unless the last clock in the chain can somehow know the error of the original ADC clock and reproduce it).

Between digital interfaces, the receiving interface collects the data packet and moves it to a buffer for further processing. Transmission jitter is gone, a group of samples are "stationary" in the buffer The next clock in the chain introduces its own jitter as the data is clocked out to the next function.

At the DAC, the sample is returned to an analog voltage level, and, again, the sample value can be decoded to an analog level early or late, and be too high or too low compared to perfection (a sample created and decoded at the "correct" time).

Ultimate analysis:

With competent gear, the samples are off by nanoseconds and there's nothing you can do about it.

Don't worry about it unless you think you can hear it, then, good luck.

Benchmark DAC2, 10 years ago or so:

1682607416514.png


1682607507313.png
 
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