I signed up for an account just to comment on this. I didn't know the forum still existed. I'm about to resurrect an old Sonar setup. The old computer died due to age related illness. It was still running Windows 2000 (long story...). Essentially I'm starting over because current computers don't support the ISA interface on my old sound card.
And that's why I've been asking the same USB 2 vs 3 question.
I was really surprised by @msmcleod's answer; dubious actually. I quickly found an article that supports it. https://www.soundonsound.com/techniques/usb-firewire-thunderbolt-which-best-audio#:~:text=The%20USB%202%20specification%20states,a%20throughput%20closer%20to%20280Mbps.
The bottom line being:
"At the theoretical maximum USB 2 bandwidth, you’d be able to record just over 40 tracks of 24-bit, 96kHz audio, while halving the sample rate to 48kHz would give you 80 tracks. Staying at 24-bit/48kHz, consider a more realistic real-world USB 2 bandwidth of 240Mbps (a slightly conservative figure, giving us plenty of overhead to allow for the connection limitations discussed earlier): you’d still have the ability to work with up to 40 channels of broadcast-quality audio simultaneously! Yet there are some companies who squeeze far higher channel counts from their USB 2 audio interfaces by building their own USB controllers. These tend to be among the more costly options, due to the extra work and design choices that go into developing and optimising this sort of solution. By way of example, RME’s MADIFace USB is a USB 2 bus-powered 128-channel digital audio interface. This is made possible by the use of the MADI protocol for handling the data transmission, which is far more efficient than the native audio-over-USB standard."
Maybe I won't wait for USB 3 interfaces after all!
