Line 6 XD-V55 Digital Wireless System with Handheld Transmitter Road-ready digital wireless system for performing vocalists Exclusive microphone modeling technology gives vocalists a choice of four superb microphone models based on the world's most popular mics 10Hz-20kHz audio frequency response with 117dB dynamic range (A weighted) One-step setup with 12 channels (up to 12 systems simultaneously) License free worldwide