- SX80 wireless microphone Sound delay: ≤30ms Microphone: -42dB±2dB omnidirectional silicon microphone Frequency response: 20Hz-20KHz Signal-to-noise ratio: ≥75dB Microphone battery/life time: 70MAH/4-5H Charging compartment battery: 300MAH Charging compartment battery charging time: about 2 hours Wokring temperature-10℃-45℃