4 inputs: 1 MIC (Lo-Z), 1 AUX (Hi-Z), 1 TEL, & 1 selectable MIC or AUX. Each input controlled by an independent volume control.
tputs for 4-ohm (direct), 8-ohm, and 16-ohm, 25V and 70V speaker systems (transformer coupled). Output jack to connect a recording device or booster amplifier, as well as an output jack to connect a general-purpose 600-ohm matching transformer (model WMT1A).
TEL input voice-activated (VOX) mute over AUX input, with variable threshold for TEL input voice-activated AUX mute. AUX muting by external contact closure for push-to-talk microphones.