 tone waveform data reading stopped state is set, the judgment result at Step SB00 is "YES". The sound source 00 proceeds to Step SB00. At Step SB00, the sound source 00 decrements the musical tone delay time T0 read from the delay time table TBL at Step SB0, described earlier (see FIG. 0). Next, at Step SB00, the sound source 00 judges whether the decremented 