In order to utilize the ADAT, you will have to get some kind of outboard converter. For a quick, cheap solution you could go with the Behringer ADA8000, as it has 8 pre-amps and can get mic or line levels into ADAT pretty easily. I used one for a while when i had an adat system, and though the preamps and the conversion aren't upper tier, for the price it is certainly usuable. There are also similar pieces by Mackie, Presonus, etc.... That scale upwards in price.