Patent ID: 7995774

Claim:
A sound field control apparatus that has multiple speakers radiating input signals to an acoustic space and multiple microphones gathering sound radiated from the multiple speakers, performs mode decomposition on a sound pressure distribution based on the output signals by the microphones, and performs control such that the mode amplitudes of modes can have a predetermined value, the apparatus comprising: a mode decomposition filter that performs mode decomposition on a sound pressure distribution based on output signals by the multiple microphones; a control filter that controls the input signals to be input to the multiple speakers such that the mode amplitudes of the modes decomposed by the mode decomposition filter can have a predetermined value; and a sound pressure distribution simulating section that measures a sound pressure distribution in the acoustic space, simulates a sound pressure distribution in the acoustic space by using a sinusoidal function and cosine function of a space frequency of the mode to be controlled in amplitude, and corrects the mode space frequency such that the simulated sound pressure distribution equals the measured sound pressure distribution, wherein the mode decomposition filter is based on the obtained mode space frequency.