The DN-470A 4-channel 70V/100V Amplifier is designed for contractor/install applications and only for installed speaker systems requiring 70V/100V inputs. This very versatile, one rack space, 120W per channel amplifier has built-in short-circuit protection and LED indicators for signal present, clipping status and thermal interruption on the front panel. Engineered strictly for the distribution of multiple 70V/100V speaker systems over long cable runs, such as in-ceiling speakers, surface-mount speakers and paging horns.