| 摘要 |
PURPOSE:To listen in a constantly good frequency characteristic independently a relation to conditions in a vehicle by measuring an acoustic place in the vehicle, comparing the frequency characteristics of an original signal with a measuring signal by means of a comparison means and controlling a correcting means for correcting the frequency characteristics by means of a control means. CONSTITUTION:Since to the frequency characteristic of an output signal from a sound receiving frequency characteristic correcting means 11, a correcting characteristic is added, the output signal does not receive the influence of the sound receiving frequency characteristic, and an acoustic characteristic in a vehicle only can be known from this output signal. In this way, a characteristic setting operation is completed. Then, in the case of regenerating an output signal from a sound source 2, at first, switches 10a, 10b are changed over to a B side, the signal from the sound source 2 is generated by the frequency characteristic set by the above-mentioned method. In this manner, one speaker is used for regenerating and as a sensor for detecting an acoustic place in the vehicle in common, the frequency characteristic is corrected according to the condition of the vehicle and thereby a constantly good acoustic characteristic for listening can be obtained without relating to the conditions in the vehicle. |
