SOUND FIELD MEASUREMENT DEVICE

摘要

A wide frequency range signal from a test sound source 1 is reproduced successively by a plurality of speakers 101 to 104, and the reproduced sound is detected by a plurality of microphones 111 and 112 , after which the frequency characteristics thereof are obtained at FFTs 4b and 4c, while obtaining the frequency characteristics of the wide frequency range signal at an FFT 4a. A high frequency range level is normalized with a low frequency range level, and a determination section 8 compares the normalized value with a reference value stored in a reference value storage section 9 to determine the number and positions of people in the sound field. At the same time, the transfer functions between the speakers and the microphones are calculated at transfer function calculators 10a and 10b, and impulse responses are obtained at IFFTs 12a and 12b, after which a reverberation time calculator 13 calculates the reverberation time based on the impulse responses. An audio signal is adjusted based on the results obtained from the determination section 8 and the reverberation time calculator 13, whereby it is possible to optimize the audio reproduction according to changes in the sound field.