Power output : L/R: 21W+21W RMS Signal to noise ratio : _85dBA (A) Noise level 25db Input sensitivity : LINE IN1: R/L:450±50mV LINE IN2: R/L:550±50mV OPT/COA: R/L:500±50mFFS Bluetooth: R/L:700±50mFFS Frequency response : 55Hz-20KHz Bass unit : 4 inch (116mm) Tweeter unit : _13mm silk dome tweeter