Williams AV IR A4 IR+ Distributed Emitter ArrayThe IR A4 is not a stand alone system and requires an IR M1 modulator and IR E4 emitter(s) to function. The IR+ features a distributed IR emitter array architecture allowing up to four emitters either stacked together for large room arrays or distributed throughout the room to accommodate wings in room design, balconies, or other obscured venue locations. Up to 16 IR E4 emitters can be connected to an IR M1 modulator with the use of the IR A4 arrays.