There is no dac chip, per se. its a discrete dac.
Regarding how to electronically measure soundstage localization given complex time-domain musical waveforms, I have given some the idea some thought but no good solution yet. Haven't read about a solution for that in any published research as of yet either. Anyone have links to share?
Regarding how to electronically measure soundstage localization given complex time-domain musical waveforms, I have given some the idea some thought but no good solution yet. Haven't read about a solution for that in any published research as of yet either. Anyone have links to share?
It does not matter what type of dac it is. Clock is only one of the components. Seemingly huge differences with close-in phase noise of clocks do not show up in phase noise at dac output.
I assume you are implying that close-in phase noise of clocks has something to do with soundstage localization. Do you know of any studies that have proven this to be the case?
I assume you are implying that close-in phase noise of clocks has something to do with soundstage localization. Do you know of any studies that have proven this to be the case?
That appears to be the case, relative to the stereo illusion. However its not the only factor. It turns out that such mundane factors such as choice of dac modulator dither can also have substantial effects. IME its only when all factors are not-excessively masking that plainly audible localization improvements become most evident. IMHO more research should be done in this area. Also IMHO, single channel power spectral measurements don't seem to be sufficient to explain plainly audible perceptual effects.
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I have measured phase noise of several dacs and clocks. Some of my earlier measurements are here. Anybody can make similar measurements provided DAC & ADC are synchronous (e.g. Cosmos ADC does not work for this).
In measuring phase noise at DAC output ADC is the limitation. But even with existing ADCs it is possible to see differences in phase noise of DAC chips. Here is a measurement of AK4493 (green) and ES9038Q2M (orange) both using the same clock and having very similar Vref and output circuit. Note that the x-scale is +/-10Hz to visualize the difference. ADC in this case was ES9822PRO.
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Thanks!
Now, I remember it was the late Jocko who indicated close-in phase noise is very important and the following here chasing this characteristic, then recently floor noise, etc. So, things are turned on its head? I wonder why then the ‘perceived’ improvement for those who upgraded their ordinary clocks to premium ones like OXCOs if DAC negates the benefits?
As I see it, it just showing THD+N mainly. Anyway of presenting the same way phase noise of clocks are done?
Where do you see THD in that? The input signal is fs/4 (11025Hz) so 2nd harmonic is not exactly on that scale. It shows close-in phase noise which includes both phase modulated (mostly clock induced) and amplitude modulated noise (mostly from Vref). Why do you think clock noise would be any different?
Yes, Jocko claimed (not indicated) that close-in phase noise is very important. But so are many other things in dacs. 'Perceived' improvements are just subjective opinions unless they have been verified with more controlled listening tests.
Well, I am not really convinced by the diy measurement system that you have cobbled up. For all you know the USB side output is jittery to start with going into the DAC (how is the clock to this device?)
Show me a proper test using an instrument grade phase noise analyser like how clock tests are done. Unless otherwise advised I will be siding with those who have done listening tests. Anyone here found little or no benefits with upgrading to premium clocks?
Show me a proper test using an instrument grade phase noise analyser like how clock tests are done. Unless otherwise advised I will be siding with those who have done listening tests. Anyone here found little or no benefits with upgrading to premium clocks?
If you believe there is something wrong with my measurement setup you are free to repeat the measurement using your own devices. Who knows, maybe they have less jitter. But proper instruments are of no use if you don't even understand what is being measured.
Apparently you have trouble reading your own posts. In my book "IMHO" which you used twice is shorthand for an opinion.
That type of power spectral measurement doesn't seem especially useful for explaining or correlating with stereo imaging. First off there are two channels, and the phase noise has an effect in the time domain with complex music signals. Why don't you demodulate the phase noise for each channel? That might actually be a start at finding a useful measurement.