| 摘要 |
PROBLEM TO BE SOLVED: To provide a public address device for suppressing the generation of sudden howling when sudden change occurs in a sound field environment and suppressing deterioration in sound quality. SOLUTION: A control unit 9 of a public address device 100 detects the generation of howling on the basis of an input signal. If the howling is generated, a variable delay circuit 10 is set so that a delay quantity may be varied. The circuit 10 varies the delay quantity at a predetermined time width and a predetermined frequency. The control unit 9 gives instruction not to release the variation to output a delay signal when the suppression of the howling is detected. Thus, the generation of the sudden howling can be suppressed, and deterioration in sound quality can be suppressed. COPYRIGHT: (C)2006,JPO&NCIPI |
