Touch Tone control of four zones expandable to 8 zones Switches line level signal to amplifiers or amplified signal to speakers amplifier s not included Balanced audio circuitry for low noise Night bell warble with adjustable level from contact closure or ringing analog line Input provided for background music Separate paging and background music level adjustments Background music automatically mutes in paged zone s in all but single amplifier mode All call and five group call patterns, selected by Touch Tones Adjustable page alert tone level Interfaces with ringing C.O. lines, Centrex lines, paging ports, unused phone system trunk inputs, or ringing analog station ports Disconnects on timeout, silence, or CPC Screw terminals for all input and output connnections