| 摘要 |
PROBLEM TO BE SOLVED: To prevent a passenger listening to the sound from feeling uncomfortable, while suppressing delay of sound volume correction for the change of noise sound volume.SOLUTION: A vehicle speed reference correction step determination unit 14 and a vehicle speed reference noise level determination unit 15 acquire the vehicle speed of a motor car detected by a vehicle speed detection unit 13. A noise difference calculation unit 16 acquires the detection noise level around the motor car detected by a noise level detection unit 11, and an acoustic correction unit 7 corrects the output sound volume. A correction step correction unit 17 controls the correction amount by the acoustic correction unit 7 on the basis of the vehicle speed thus acquired, and the noise difference between a vehicle speed reference noise level estimated based on the vehicle speed thus acquired, and the detection noise level thus acquired. |
