Description: *Output power: add pre-5532 output foot powered 25V, powered 25V,6? impedance output 2x50w, 8? impedance output 2x40w dual-channel *Power: 2.1 interface 8-25v DC power supply *Chip: tda7492p,the Sound Quality is very good, big power. *Output impedance: 8 ?(best), 4/6/8/16? impedance can drive speakers *DIP switches can be adjusted directly after the amp Gain more respect and Better promote greater damping horn Package Includes: 1 Piece tda7492p Bluetooth 4.0 audio receiver amplifier board