2 ch analog in (2 XLR/TRS combo line or 2 XLR mic), 2 analog out (2 XLR or 2 TRS), 2 inserts (2 TRS), 2 Haufe mic preamps, tube compressor/limiter, 4-band parallel EQ, various digital i/o on optional cards. USB connection requires DI-MOD USB option ($449 list), which adds A/D to this analog device.