Two versions with either 20W or 40W output & both with 230 Vac mains & 12 Vdc operation make these amplifiers suitable for use in a wide variety of small & medium-sized public address systems. There are two balanced microphone inputs. A jack socket is provided on the front panel for mic one. Mic two has a voice activated priority circuit to automatically mute all other inputs. There are two auxiliary inputs for background music. Either 70V 100V line or low impedance 8andohm loudspeakers can be used. Separate mic 1 bass treble & a dual auxiliary control are located on the front panel.