The Silent Symphony-Duo-Talk from VocoPro is a two-receiver stereo wireless listening system that broadcasts in stereo via a high-definition transmitter for superior sound. The transmitter connects to the included headset microphone to speak to all wireless headphones without additional PA equipment. The wireless headphone receiver and high-definition stereo transmitter operate in 900mHz (908.70–926.30mHz), clear of TV, radio and Wi-Fi interference.