I was referring to the fact that in each individual speaker, AD and DA are in sync.
When the chain ADC-->DSP-->DAC is all running from the same clock it doesn't really matter what that clock rate is or if it is the same as other such clocks (e.g. in the other loudspeaker(s)). Samples will just march through and come out the other side. The rate is only affecting things like the Nyquist frequency, which has nothing to do with synchronicity.
When you get into trouble is when different parts of the chain run at a rate that is different than other parts of the chain. The typical example of this is an asynchronous USB DAC. It has its own clock inside. That clock will not run at the exact same rate as the clock inside the computer that is controlling DSP. There may be yet another clock governing the ADC. At some point the different rate of sample production and consumption lead to buffer over/under runs. Also, the actual playback rate is controlled solely by the DAC clock. When there are multiple asychronous DACs (in our example on for each speaker) and each has their own clock, now the playback rates and thus the exact sample that is being produced at any one instance will be different from DAC to DAC, speaker to speaker. They are out of sync. At 48kHz each sample is a chunk of about 20usec, and after a synchronization difference of around 20 of these you start to get audible effects (stereo image panning all the way to one side, etc).
When you get into trouble is when different parts of the chain run at a rate that is different than other parts of the chain. The typical example of this is an asynchronous USB DAC. It has its own clock inside. That clock will not run at the exact same rate as the clock inside the computer that is controlling DSP. There may be yet another clock governing the ADC. At some point the different rate of sample production and consumption lead to buffer over/under runs. Also, the actual playback rate is controlled solely by the DAC clock. When there are multiple asychronous DACs (in our example on for each speaker) and each has their own clock, now the playback rates and thus the exact sample that is being produced at any one instance will be different from DAC to DAC, speaker to speaker. They are out of sync. At 48kHz each sample is a chunk of about 20usec, and after a synchronization difference of around 20 of these you start to get audible effects (stereo image panning all the way to one side, etc).
Actually the DSP in a regular PC is (typically) controlled by the clock of the output device as the output driver sets the pace of samples consumption -> processing.
That's exactly where the problem arises. Or an incoming network stream which has no rate feedback (rtp etc.).
I have a 7.1 HDMI audio extractor and another 5.1 HDMI audio extractor on hand... If it's not to much trouble, could you tell me how to configure individual channels to 2 separate HDMI outputs in Windows? (essentially to make a 12.2 pre-pro?)
Maybe try a google search for 'virtual audio cable for windows 10' or something like that. Some virtual audio cable apps may offer the type of routing options you want.
I could understand a little audio hardware, but software is a whole other thing my brain can't process lol I tried Virtual Audio Cable (VAC) from muzychenko net.. but Nothing made sense to me. I was able to get a few virtual line outs but that's the extent of what I understood of that program, hit a wall there
Well, there is more than app to try. Also, I guess lots of things may have some learning curve for different terminology, conceptual functionality, etc. If you want, collectively could we probably talk about it enough here in the forum for it to start to make more sense.
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I can't be of any assistance, I'm afraid. The last windows version I used was XP, I switched over to Linux in 2006. What little I remember of the Windows audio stack is probably wrong and of no use nowadays.