US Patent 8411883 Loudspeaker apparatus and speaker system

A loudspeaker apparatus includes a speaker array that has a plurality of speaker units which are arranged on a sound emitting surface of the speaker array, and emits sound beams on a plurality of channels, an angle sensing section that senses an angle change displaced from a previously set reference angle of the sound emitting surface, and an adjusting section that adjusts output angles of the sound beams in response to the angle change.