> Holy crap, that's a lot of input channels
96 output too. I have a lot of outboard gear, my SSL Sigma Delta alone is 32 in/out for mixing, that's before I get onto all my outboard compressors, EQs, reverbs, synths, drum machines, and modular gear. I use the soundcard pretty much as a virtual patch-bay, I can send and return to any piece of gear in my studio like a plugin (get Bitwig to measure the latency and automagically everything syncs).
> You are obviously more advanced than me, not sure what you mean here.
Because digital audio is in discrete time-slices, you need to sync the slice starts so all devices are aligned. Otherwise you can have subframe issues where phasing becomes a problem - in the worst cases it can cause audio glitches (which I've had with older AD/DA convertors).
This can be solved by using a Word Clock [1], which is the 'old' way, or via AES/MADI/Dante - which all have their own clocking protocols. The devices all need to be clocked by the same source, which you can't do by pairing devices in software.
My current soundcard is connected, via MADI, to my 3xFerrofish-A32-Pro AD/DA units. The soundcard is the source of truth for timing. The AD/DA devices all sync to the soundcard and therefore have no phasing issues. This gives 96 channels of analogue audio in and 96 channels of analogue audio out.
> I've had earlier problems with PCI cards, in that they pick up a lot of internal noise from the motherboard
Sure, if you plug analogue sources directly into the device. But my analogue inputs/outputs are all going into my AD/DA convertors, which are separate units. They are digitising the audio and by the time it arrives (via MADI) into my soundcard it's already digital. That means no chance of any noise from the computer.
Probably what I need is something like this [2], it seems to have Linux support, but unfortunately isn't produced any more! I seem to find that a lot with these Dante devices. Maybe I'd be better with AES67 as that's an open-standard that is compatible with Dante, just I haven't found anything yet!
In theory (because Dante/AES67 is over IP) a virtual soundcard can be written, I certainly have a powerful enough machine to run it, but again I haven't found anything yet. I'd write it myself, but I have a million things going on, and that's a distraction I don't need!
It does seem like there's a bit of a gap when you get to the real pro end of audio, which is a shame because the stability of Linux would is a huuuuuge selling point when producing music.
[1] https://en.wikipedia.org/wiki/Word_clock
[2] https://www.audinate.com/products/dante-enabled/four-audio/f...