Hercules XPS 2.1 20 ARC. Audio output channels: 2.1, RMS rated power: 8 W. Satellite speakers RMS power: 4 W, Satellite speaker frequency range: 50 - 20000 Hz. Subwoofer type: Active, Subwoofer RMS power: 4 W. Power source: AC. Satellite speaker dimensions (WxDxH): 65 x 65 x 238 mm, Subwoofer dimensions (WxDxH): 130 x 170 x 215 mm