KEY FEATURES · Up to 18,000 square feet (1673 m 2 ) of coverage using high- efficiency infrared LEDs · Two Phoenix-style line-level inputs and one 3.5mm micro - phone input · Provides for one- or two-channel operation · Flexible channels -- operating frequencies of 2.3/2.8MHz or 3.3/3.8MHz are supported in one unit. · Use both channels (A and B) for high-quality stereo output · Compatible with Williams Sound infrared receivers (WIR RX18 and WIR RX22-4N) · Commercial-grade design for indoor environments · Easy-to-read power status and audio input indicators on rear panel · Power-saving mode turns the unit off after no audio is pres - ent for 12 minutes. · Wall/ceiling mount bracket included. Top or bottom mounting option. · Phoenix-style connectors to RS232 · Serial bus for integration with room control systems that monitor health of the unit, as well as control power and audio.