20KHz. Running Temperature level: -10 ～ 55 ℃. Dimensions: 126x66x27mm. Network Digital Amplifier XC-9508P Power Supply: AC100V ～ 240V, 50/60Hz. Power: 130W, 260W, 360W, 500W. Communication Protocol: TCP/IP, UDP, SIP. Signal-to-Noise Proportion: > 80dB. Regularity Action: 60Hz https://bluetoothspeaker94714.bloggazzo.com/29424605/the-function-of-an-ip-paging-microphone-in-effective-work-environment-communication