I just read the promo info on the M-Audio Firewire 1814, and I'm still not sure which part tells me it will record 4-8 channels separately.
Forget the really old stuff like the UA5. The 1814 is modern with USB 2.0. Plenty of bandwidht there.
The Firewire 1814 can transfer 8 signals to the computer at the time. Add an extra box with ADAT (exampel Behringer ADA8000) and you can transfer 16 signals in to the computer. All at the same time. Now, if you add one more box with an SPDIF signal, you might be able to get 2 more channels at the same time. That is 18 concurrent signals at the same time.
There are however two things that has to be true in order to get 18 concurrent channels (each into its own track).
- max sample rate 48kHz. Reason is that on an ADAT cable you get only 4 channels (not 8 ) on 88.2 and 96kHz. And with this box, if you run at 192kHz the ADAT will not work at all.
- if you want to run both 2 inputs via SPDIF and 8 inputs via ADAT (plus the 8 analog) you will probably need to synchronize the clock in a bit special way. Reason is that most 2 channel boxes with SPDIF output lacks the synch input so they need to be set as master. (Now all this is very special, simply forget it for the moment).
How many channels your computer can handle is another thing. There is a lot of interacting factors here, especially around exactly how the USB2.0 interface is done in the computer. Older computers, say more than 3 years old, have more problems than modern ones. When running Windows there is also a lot of talk about problems with Vista, but then again some people run it just fine.
Complicated, indeed. Good questions though. Keep them coming.
// Gunnar