The USB mixer amplifiers have power ratings from, 60W, 120W to 240W. They are featured of three balanced microphone inputs, two aux inputs and one EMC input. Priority muting is achieved via EMC input for overriding other inputs except Mic1 on front panel. Individual gain controls are provided for Mic 1-3 and Aux 1-2, bass and treble controls and master volume control are provided for overall tone control. 70V, 100V and low impedance 4-16ohms speaker outputs are provided. Extensive protection from short-circuit, overload and high temp.