WMIs are flush-mounted wall microphone input units that can be integrated into various types of installation materials for system integration. They are equipped with a female XLR input connector on the front and a terminal block connector on the rear. The signal applied to the input connection is converted into a differential signal with increased voltage levels.

This way, the signal becomes insensitive to interference and noise and can be transmitted over long distances without loss of quality. This enables reliable signal transmission up to 300 meters via CAT5E (or better) twisted-pair cabling. A jumper on the rear panel enables 15-volt phantom power. It must be used in conjunction with a corresponding device at the receiver end.