The BMB IR-B Dual Wireless Microphone is the 3MHz version (2MHz IR-A Model Also available) of BMB's professional system.Dual IR Sensors are used to create a full coverage area to use the microphones within.One IR sensor is pre-installed on the microphone receiver but can be relocated if needed,You'll then need to select the best spot for the second IR sensor depending on your environment.This provides better coverage the oter wireless systems where  you need a clear line of site from the microphone to the receiver.With this system,you may have an IR sensor capturng your voice in front and behind the microphone so obstructions have less of chance of interrupting your performance.You can keep microphones charged up and ready for use simply by placing them in the charging base.Rechargeable batteries are included. 

The advantages of using infrared microphones are that it eliminates the possibility of radio frequencies interfering and provides trouble free operation in environments where multiple wireless systems are required.Since you are using another technology altogether,radio broadcasts from TV stations,radio stations, or typical wireless microphone system will not cause interference.The 2nd Huge advantage is in venues where multiple sets of infrared microphones are used in rooms that are separated by walls. Infrared wont penetrate through walls so it won't interfere with another set next door.The best applications are in karaoke bar rooms,classroons,restaurants private dining rooms,or any place you can set up the IR coverage area.