| 摘要 |
PURPOSE:To improve the howling suppression effect by providing a frequency analyzing part of the noise in a room and a filter part, which control its frequency characteristic in accordance with the analysis result, to define a color noise having the frequency characteristic matched to the noise in the room as a transmission characteristic estimating sound. CONSTITUTION:A switch 11 of a howling suppressing device is connected to the B side before loudening, and the noise in the room is gathered by a micro phone 1 and is amplified by an amplifier 2 and has the frequency analyzed by a frequency analyzing part 12. The result of this frequency analysis is applied to a filter 13, and a switch 14 is closed to change the frequency characteristic of the filter 13, and the gain of a frequency band having a higher level is con trolled to a higher value. Next, the switch 14 is opened to inhibit the change of the frequency characteristic, and the switch 11 is connected to the C side to estimate the transmission characteristic, and thereafter, the switch 11 is connected to the A side to louden sounds. The color noise having the frequency characteristic matched to the noise in the room is defined as the transmission characteristic estimating sound, and howling in all frequency bands is suppressed. |
