| 摘要 |
<P>PROBLEM TO BE SOLVED: To allow stereo recording at a high sound quality. <P>SOLUTION: An A/D converter 10 converts analog audio signals of L channel and R channel to digital audio signals respectively. A volume circuit multiples the digital audio signals of L channel and R channel with gains G1L and G1R which are adjustable respectively. A control part 40, in a calibration mode, makes a peak detection circuit 22 active so as to obtain a peak value S3 of the digital audio signals of L channel and R channel. Then the control part 40, according to a difference between a peak value S3L of L channel and a predetermined reference value REF, calculates a gain G1L of L channel which is to be set in the volume circuit during a normal mode, and calculates a gain G1R of R channel which is to be set in a volume circuit 24 during normal mode according to a difference between a peak value S3R of R channel and the reference value REF. <P>COPYRIGHT: (C)2013,JPO&INPIT |
