Power amplifier with power rating of 120 W RMS, with speakers output of 100 V, 70 V or 50 V, or low impedance (4, 8 or 16 ohm). It has audio inputs/outputs of program and priority (0 dBu and 600 ohm) with independent volume control. Incorporates the security paging function and protection circuit against overload, overheat and short circuit in the line of speakers. Compatible with the surveillance unit SU-114N. Two rack units.