USB Audio Interface, 28-in/30-out with 8 500 Series Slots, Monitor Control, Cue Mixer, ADAT and MIDI I/O, Analog Summing, (2) 500 Series Mic/Line/Instrument Preamps with Selectable Input Impedance, Variable Coloration, Highpass Filter, and (2) 3-band 500 Series EQs with Harmonic Saturation Technology, Optosync Feature