| 摘要 |
PURPOSE: To eliminate affecting a recording medium by a noise caused by the wind by utilizing microphones electronic circuits are postpositively connected thereto respectively, continuously measuring the air pressure during the sound recording, and selecting the most senseless microphone against a wind noise among plural individual microphones adjacently aligned. CONSTITUTION: The flow of the air generated by the microphone Mw for measuring the wind pressure and a voltage proportional to a sound pressure equivalent to the wind are amplified by a prepositioned amplifier 4, and filtered in a low- pass filter 5 into the frequency component approximately >=250Hz. Then, the wind strength in the microphone Mw is detected in a detector 12, and switches 6, 7 and 8 are turned on in a logic evaluating part 11 each time. The switches connects the most senseless microphones M1, M2 or Mn against the strength of the generated wind to the amplifier each time, respectively. Here, the separated microphones M1, M2 and Mn are a pressure microphone and/or a pressure- gradient microphone and/or a tube directivity microphone adjacently aligned. |
