SilentSymphony-Seminar-Talk from VocoPro is a 30-receiver stereo wireless listening system that broadcasts in stereo with 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. This SilentSymphony-Seminar-Talk is great for DJs putting on "silent" dance parties.