| 摘要 |
PURPOSE:To simply set up a loop section, to prevent the deterioration in sound quality and to suppress the increment of the size of a sound source in a waveform reader for reproducing a loop from waveform data stored by a DPCM system and forming a musical sound. CONSTITUTION:Respective difference values of acoustic signals stored in a waveform ROM 102 are successively integrated from a start address. When the address exceeds an end address, the address is folded to the loop start address side. An integration value computed at the time of the loop start address is stored in the end address, and at the timing of returning the address from the end address side to the loop start address side, the computed integration value is substituted for the integration value stored in the end address. Difference values read out again from addresses following the loop start address are successively integrated by using the obtained integration value as an initial value. |
