| 摘要 |
PROBLEM TO BE SOLVED: To always realize an optimum time alignment function without errors by changing a sound velocity value used for calculation for setting delay time in accordance with a temperature situation and setting optimum delay time. SOLUTION: When sound velocity is changed by the temperature change, a control part 1 calculates delay time which is to be given to the sound signals of respective channels, which correspond to that time. The delay time of the respective channels is multiplied by the value of a sampling frequency in an A/D converter 21 in the delay time of the respective channels and delay time is converted into the number of delay samples as a value for controlling delay quantity in DSP 22. The number of the delay samples of the respective channels is set in DSP 22 and DSP 22 delays and outputs the signals of the respective channels in accordance with the number of the delay samples which are set on the sound signals of the respective channels. Thus, the time alignment function becomes valid and a state where all speaker units are artificially in equal distances is realized in a driving seat, for example. |
