| 摘要 |
<P>PROBLEM TO BE SOLVED: To improve S/N characteristic at the time when an analogue signal for which a large headroom is set is amplified with a digital processing circuit. <P>SOLUTION: Audio processing systems 11-1n include an analogue amplification circuits 21-2n, AD conversion circuits 31-3n, and digital processing circuits 41-4n. The analogue signal inputted in the first audio processing system 11 is distributed to the analogue amplification circuits 21 and 22 of first and second audio processing systems by way of a distribution switch 62. The distributed analogue signal is, based on a headroom having been set to be 26 dB, amplified by the analogue amplification circuits 21 and 22, and is converted to the digital signal of -26 dBFS by the AD conversion circuits 31 and 32. These digital signals are inputted in a digital signal addition processing circuit 40 by way of selecting switches 71 and 72. These digital signals are added and amplified at the digital signal addition processing circuit 40, and is outputted as the digital signal of -20 dBFS which is the output level of general standard. <P>COPYRIGHT: (C)2012,JPO&INPIT |
