51 speaker system transmission mode cable number of speakers 6 components 1x subwoofer 2x surround 1x centre 2x front impedance 6 ohm front speaker type magnetically shielded front enclosures 1x 80mm subwoofer 1 x 25mm tweeter music handling capacity front 130 watt central speaker type magnetically shielded central enclosures 2x 80mm subwoofer 1x 25mm tweeter music handling capacity centre 130 watt subwoofer types active ground emitter subwoofer function