| 摘要 |
PROBLEM TO BE SOLVED: To provide the noise-sensitive volume control in which the operation of correction is indicated, in response to noise. SOLUTION: An output of a CD player 11, being a sound source and a sound volume in a vehicle chamber picked up by a microphone 12, are received by a microcomputer (μP) 10. A noise sound volume in the vehicle chamber is calculated by subtracting the sound source sound volume, attenuated by setting of an operation device 17 from the sound volume in the vehicle chamber. The sound source sound volume is corrected depending on the noise sound volume, the result is outputted from the μP 10 and the output is sounded from a speaker 16, via an electronic volume 14 and an output amplifier 15. Furthermore, the setting of the electronic volume is changed by the operation device 17. Since the sound volume in the vehicle chamber is outputted from the μP 10 and indicated on an 8-segment LED for example, in numerals, the user recognizes that a correction due to noise is being made. |
