| 摘要 |
PURPOSE:To clearly bring a target voice to sound recording by reducing a wind cutting sound by using two or more pieces of microphones whose sensitivity to the wind cutting sound is different, and detecting whether the wind cutting sound exists or not by a difference of output signals of the microphones. CONSTITUTION:A microphone 1 whose sensitivity to a wind cutting sound is high, and a microphone 2 whose sensitivity is low are given to a mixing circuit 5 through voice circuits 3, 4, and mixed, based on a control signal S1 of a control circuit 14. A mixed output is selected by a control signal S2 by a switching circuit 7 through an HPF 6 or a direct path, and sent to a sound recording circuit system. Also, from outputs of the voice circuits 3, 4, a low-pitched sound area being a main frequency component of the wind cutting sound is extracted by LPFs 9, 10, detected converted to a DC voltage by detecting circuits 11, 12, and thereafter, inputted to a comparing circuit 13, and when a level difference exceeds a prescribed value, it is discriminated that the wind cutting sound exists. When the wind cutting sound exists, the control circuit 14 generates a signal S1 and raises an output ratio of the microphone 2, generates a signal S2 and switches a switching circuit 7, and attenuates and outputs a wind cutting sound component through the HPF 6. As a result, even under a strong wind, sound recording can be executed satisfactorily. |
