the at-mx351 smartmixer�is a microprocessor controlled, automatic switching, five-channel mixer. the four microphone inputs are xlrf-type balanced, with 48-volt phantom power available on pins 2 and 3. the aux input is an rca jack accepting auxiliary-level input from sources such as tape decks and vcrs. there is no signal processing of the aux input. the mixer output is xlrm-type balanced, non-inverting.