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Looking for a treatise on jitter relationship to stereo imaging


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Files that are recordings certainly have the recorded waveform altered by the effects of jitter. Whether that jitter altered the waveform when it was captured by the ADC or whether the waveform is altered by the DAC upon playback. The result is the effects of jitter.

 

BTW, this can also happen as the CD stamper approaches the end of it's serviceable life.

 

How a Digital Audio file sounds, or a Digital Video file looks, is governed to a large extent by the Power Supply area. All that Identical Checksums gives is the possibility of REGENERATING the file to close to that of the original file.

PROFILE UPDATED 13-11-2020

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Not trying to be obtuse, rather trying to be precise and not trying to make, nor accept, assumptions. By "model" I mean that you are not directly measuring jitter, rather something else that is affected by jitter. What types of changes in the file are caused by what types of jitter. I don't want people to get the idea that jitter is a properly of a file or filesystem -- well if there is jitter as measured by an eye pattern in Ethernet transmission that is *entirely different* than jitter in an ADC -- the effects of which, yes, can be obvious in a recording.

 

Clearly there are many types of jitter and I'm not clear that this measurement technique is capable of differentiating. That's why I asked how the technique was validated, and for what types of data/jitter. I think that is a very reasonable question. So the farther you get away from the exact thing you are trying to measure, and the more assumptions you make, and the more other factors that you dismiss, the less confidence that I have that your measurements are valid ... by yes I agree that broadly "jitter" in the ADC results in changes in the recording, and "jitter" in the DAC result in changes in the analog output. Serially playing and recording has the possibility of introducing interactions between the ADC and DAC clocks that are rather unlikely audible when just recording and playing back (once). For example, the two clocks could have an absolute frequency accuracy that might differ by 1% and this would be inaudible. I personally focus on minimizing close-in phase noise. YMMV.

 

The difference in clock speeds in the case of my files was .00578% which puts it a touch over .046% by the 8th generation. The title of that thread was some hyperbole. It wasn't intended to be a precise measure of jitter. Rather about whether you could hear 8th generations of total degradation. As the speed change was low enough not to matter, the distortion was low enough not to matter and frequency response was close enough not to matter, then jitter was much higher by some unknown amount. My supposition is also low enough not to matter. But no that wasn't really a careful measuring or exhibition of precise jitter differences. Nor was that the main purpose.

 

If 8 generations of whatever degradation occurs is not discernible (and for me at least it isn't) then one can cease to worry about any of those things when playing back files or when recording them. The recording degradation was actually where my main interests were in this particular instance.

And always keep in mind: Cognitive biases, like seeing optical illusions are a sign of a normally functioning brain. We all have them, it’s nothing to be ashamed about, but it is something that affects our objective evaluation of reality. 

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BTW, this can also happen as the CD stamper approaches the end of it's serviceable life.

 

Whether a stamper putting out barely readable CDs starts to effect jitter output I don't know. It doesn't change the digitally encoded waveform however in the manner re-recording a file does.

And always keep in mind: Cognitive biases, like seeing optical illusions are a sign of a normally functioning brain. We all have them, it’s nothing to be ashamed about, but it is something that affects our objective evaluation of reality. 

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Whether a stamper putting out barely readable CDs starts to effect jitter output I don't know. It doesn't change the digitally encoded waveform however in the manner re-recording a file does.

 

https://www.google.com.au/?gws_rd=ssl#q=jitter+due+to+CD+stamper+wear

 

How a Digital Audio file sounds, or a Digital Video file looks, is governed to a large extent by the Power Supply area. All that Identical Checksums gives is the possibility of REGENERATING the file to close to that of the original file.

PROFILE UPDATED 13-11-2020

Link to comment
The difference in clock speeds in the case of my files was .00578% which puts it a touch over .046% by the 8th generation. The title of that thread was some hyperbole. It wasn't intended to be a precise measure of jitter. Rather about whether you could hear 8th generations of total degradation. As the speed change was low enough not to matter, the distortion was low enough not to matter and frequency response was close enough not to matter, then jitter was much higher by some unknown amount. My supposition is also low enough not to matter. But no that wasn't really a careful measuring or exhibition of precise jitter differences. Nor was that the main purpose.

 

If 8 generations of whatever degradation occurs is not discernible (and for me at least it isn't) then one can cease to worry about any of those things when playing back files or when recording them. The recording degradation was actually where my main interests were in this particular instance.

 

Fair enough and certainly if looking at your main interest. No quibble with "total degradation" ;)

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