ITC TS-0300GC Fully Digital Conference System Host, Microphone capacity: (30 wired microphones; 30 wireless microphones), Frequency response: 80HZ~16KHz, Signal-to-noise ratio: >80dB(A), Dynamic range: >80dB, Total harmonic distortion: <0.05%, DELEGATES output interface: 3 channels, used to connect wired conference speaking unit, RS-232 interface, RS-485 interface, 2.0-inch TFT LCD screen, 110-250V AC.