The MCP 5500 was the updated version of the MCP 5000 and was easily distinguished by the rotary controller which was used primarily for volume control but also had secondary functions enabled allowing treble, bass and balance to be controlled.
Unlike the MCP 5000, it used what were essentially Beolink 1000 codes but required an additional code to be sent by the Beomaster to allow two way control. Only the Beomaster 5500, 6500 and 7000 provided these signals so it was of limited value with other systems.
It was available in white to match the Whiteline 5500 system.