Abstract: A signal distribution and communication arrangement includes an electronic processor-based master control unit which controls the broadcast of different types of signals through speakers located in various zones. The system includes a telephone interfaced with a door speaker controller to allow communication between the telephone and a door speaker. A page may be broadcast over the speakers and subsequently muted to allow private communication when the page is answered. Also included is a doorbell interface circuit that responds to a doorbell source. The doorbell source may be activated by any one of a plurality of doorbell switches.

Abstract: A loudspeaker enclosure which is adapted to be easily assembled with other like enclosures. The loudspeaker enclosure comprises a front wall through which sound can emanate, two essentially parallel end walls, each end wall being in the shape of a trapezoid and a back wall. The enclosure further includes two side walls extending between the end walls, each of the side walls having a plurality of outwardly projecting linear ribs extending on a line between the front wall and the back wall.