METHOD FOR MEASURING ACOUSTIC FEELING CORRECTION CURVE OF PARAMETRIC ARRAY SPEAKER AND PARAMETRIC ARRAY SPEAKER DEVICE

摘要

PROBLEM TO BE SOLVED: To improve the sound quality of differential frequency components (self-demodulation sound) generated by modulating the carriers of ultrasonic waves by audio signals and outputting them by a parametric array speaker.;SOLUTION: Signals of at least one reference frequency component are taken out from input audio signals, and the signal level of the frequency component is detected once or more. On the basis of three discrimination signals which are a discrimination signal A outputted in accordance with the detected signal level, a discrimination signal B outputted in accordance with a set modulation degree and a discrimination signal C outputted in accordance with a set amplification factor, an acoustic feeling correction filter for changing the level of the input audio signals for each frequency so as to match the acoustic feeling correction curve for the self-demodulation sound is selected and mounted. The carriers of the ultrasonic waves are modulated by audio signals which have passed through the acoustic feeling correction filter, amplified in an amplifier and then emitted by the parametric array speaker.;COPYRIGHT: (C)2007,JPO&INPIT