Optimize the sound and performance of any overhead paging system with Mackenzie Laboratories' (Booth 840) new OPM-3SM, multiple channel page stacker, feedback eliminator and messaging system. OPM-3SM simultaneously records and stores three channels of incoming pages then plays them back sequentially. A dedicated messaging system allows touch-tone or contact closure access to pre-recorded announcements. A BGM interface allows background music to be output to the public address system when no pages are being made.