5.1-channel amplifier Real 5.1-channel input/output Highly magnetically shielded 6-channel separate remote control Tower speaker made of plastic Tower speaker: Drive unit: 2 inches x 4 Frequency: 250Hz-20kHz Sensitivity: 87dB Impedance: 8 ohms Power: 20W Subwoofer: Drive unit: 8 inches Frequency: 38Hz-250Hz Sensitivity: 87dB Impedance: 8 ohms Power: 60W (RMS) THD: <1% decoder or FM radio (optional) 2.4GHz wireless surround speaker (optional)