| 摘要 |
PURPOSE:To allow a driver to obtain a desired sound image location by automatically changing a tap of an FIR filter depending on a state of a space in a cabin so as to correct a sound field optimizingly. CONSTITUTION:When start of an engine is detected, an impulse transmitter 151 selects sequentially switches 121 to 124 and gives an impulse signal to speakers 31 to 34 via amplifiers 21 to 24 and a sound wave is emitted to a cabin 41. Microphones 131, 132 arranged in the vicinity of both ears of the driver send an impulse tone to a filter tap arithmetic unit 141, which stores a transmission characteristic from the speaker to the microphones. A tap of FIR filters 111 to 114 is calculated to obtain an impulse response equal to an object characteristic by a filter tap arithmetic means 144 based on a desired acoustic characteristic stored in advance in an object characteristic storage means 144, the tap is set and the switches 121 to 124 are thrown to the position of the FIR filters. Thus, the driver obtains a desired sound image location. |
