PURPOSE: To prevent both high and low frequency band component level detectors from detecting the erroneous levels due to the variance of the center potential of each filter output.

CONSTITUTION: A high frequency band component level detector 14 and a low frequency band component level detector 15 detect the high and low frequency band component levels of the output of a microphone 1 via an HPF 2 and an LPF 3 respectively. Then a sound collector detects the generation of wind noises based on the levels detected by both detectors 14 and 15 and then attenuates the low frequency band component when the wind noises are generated. In such a constitution, the output of the microphone 1 is supplied to a mute circuit 22 only for a certain period of time after the power source is supplied to a system. Thus the AC component is eliminated out of the output of the microphone 1, and this output is inputted to the filters 2 and 3. Then the center potential of each filter output is stored in a reference potential memory. The output of the microphone 1 is directly inputted to both filters 2 and 3, and the center potential stored in the memory is subtracted from the detection output of each filter. These subtraction outputs are defined as the high and low frequency band component levels.