Note that when using non-audio oscillators, jitter is determined more by the PLL than by the oscillators.
Alex.
Alex.
I mean a frequency that is not a multiple of sampling. BTW this oscillators are proposed for audio by manufacturer,
Close-in phase noise is a different consideration from slow frequency drift. It is the close-in phase noise that Andrea Mori and others were trying to minimize.
Minimizing close-in phase noise is similar to any effort of optimization. At some point the costs vs. gains cannot be justified. There is no guarantee that with ES9039Q2M in ASR mode clocks having lower close-in phase noise than e.g. Kyocera KC7050 would make such an audible difference that it could be reliably identified in controlled listening test. Same goes with synchronous mode. So far there are no studies or controlled listening tests showing audible difference between well implemented and well measuring DACs or clocks having low vs. ultra low close-in phase noise.
Yes - one causes analog pitch change - you need a pretty good music ear to catch that 😉 (read impossible) - but the other one....
Explain again how the close-in noise effects the listening experience for you?
And let's repeat how such noise, say -80...-100 (dBc/Hz) at 1...10 Hz, technically manifest itself on the analog side - i.e. the output of a DAC:
- is noise added (i.e non harmonic additions)? How and how much?
- is distortion added (i.e harmonic additions)? How and how much?
- is FR changed? How and how much?
- is phase changed? How and how much?
- any other relevant analog signal characteristic I missed?
tnx!
//
Thanks, now understand. So, I have two sources, SA9227 (with 45.158 and 49.152Mhz NSC5083D) and XU208 (with 22.5792 and 24.576 same model XOs) and will have an opportunity in a few weeks to compare them as MCLK with ASR mode on oscillators at non-audio frequencies.
My board was configured in ASYNC not by myself, and just thought about to compare it now. If I want to put external 45.15/49.152 MCLK which HW right mode should i choose, #8? What does it mean #11 SYNC and ACG ?
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Yes. Pretty much everything that matters. This stuff and the preset state of the art in dac measurements has been discussed many times, including with links to and or attached scientific papers. For one example, the present state of the art does not include a good, standardized way to measure sound stage. I am not going to repeat the whole body of literature and discussions here. If someone wants to discuss some particular issue they would be welcome to PM.
As has been discussed before sound stage is a subjective illusion. Typically such illusions or anything else subjective are impossible to measure.
There is, "Objective assessment of phantom images in a 3-D sound field using a virtual listener," by Hawksford. There is other published research on localization cues as well. What we have is some of what we need for comprehensive objective measurements of sound stage. There is more work to be done, is all.
Note that virtual listener is not human. So your subjective claims regarding sound stage do not apply.