The Whirlwind Micmute Foot Pedal Microphone Muting Box is an active, completely silent. The circuitry allows the user to temporarily mute the mic signal with no audible artifacts even when the console channel is set at high gains. In addition, the Micmute PX can be configured to operate in any of the switching modes: PT (Push to Talk), PM (Push to Mute) or PP (Latching Push On; Push Off). This provides a one box solution for any microphone muting application by simply moving the internal jumper to set the desired function. The Micmute PX features a heavy-duty footswitch that is also suitable for finger operation on a desktop. The unit has a female XLR input and a male XLR output jack. When no signal is passing through the box, the output jack is configured to mute the input of the connected audio device.The PX has an indicator LED feature. The blue LED illuminates to indicate that the mic is ON and signal is passing through the box. Quiet 48 Volt phantom power is supplied by the Micmute PX, so any condenser microphone can be used. A rear panel switch turns the phantom power on and off. Power requirements are 24 VAC/100mA.The switching mode of the MicmutePX can be changed by moving a jumper plug, located inside the unit. Remove the four screws holding the unit together and locate the three 2 pin headers on the right side of the circuit board. They are labeled PP (Latching Push On; Push Off), PT (Push to Talk) and PM (Push to Mute). Move the jumper to the header