Patent ID: 8116488

Claim:
A sound reproducing apparatus for use with a sound signal source, said sound reproducing apparatus comprising: a first unit including: a first power amplifier connected to the sound signal source; a first speaker connected to the first power amplifier; a first phase shifter connected to the sound signal source; a second power amplifier connected to the first phase shifter; a second speaker connected to the second power amplifier, wherein the first phase shifter phase-shifts the sound signal source to reduce interference between output signals of the first speaker and the second speaker; and a second unit including: a second phase shifter connected to the sound signal source; a third power amplifier connected to the second phase shifter; a third speaker connected to the third power amplifier; a third phase shifter connected to the sound signal source; a fourth phase shifter connected to the third phase shifter; a fourth power amplifier connected to the fourth phase shifter; and a fourth speaker connected to the fourth power amplifier, wherein the third phase shifter phase-shifts the sound signal source to reduce interference between output signals of the third speaker and the fourth speaker, wherein the first speaker and the second speaker are in right and left relation with each other with respect to an area; the third speaker and the fourth speaker are in right and left relation with each other with respect to the area; a first group of the first speaker and the second speaker is positioned in a front of the area and a second group of the third speaker and the fourth speaker is positioned in a rear of the area; and the second phase shifter and the fourth phase shifter phase-shift the sound signal source to reduce interference between output signals of the first group of the first speaker and the second speaker and output signals of the second group of the third speaker and the fourth speaker.