| 摘要 |
PURPOSE:To carry out a startup control of an output, a stabilization of the output amplitude, and the like, sufficiently without oscillating a loop circuit by controlling the input level of a drive waveform input from a drive waveform output circuit to a closed-loop circuit depending on the musical sound synthesis output of the closed-loop circuit. CONSTITUTION:A music sound control data generator 1 delivers various control signals of the performance data to various parts of the circuit, a drive waveform is input from a drive waveform generator 2 to a closed-loop circuit 11 through a multiplier 8, and the drive wave form is circulated through the closed loop. The level of the music sound signal picked up after circulating in the closed loop is detected by an envelope detector 3, and the music sound signal is output to the multiplier 8. The control output to the multiplier 8 is regulated by a level regulating signal beta. The drive waveform is controlled its input level by the multiplier 8, and the amplitude of the drive waveform input is controlled while watching the output waveform of the circuit 11. As a result, it is made possible to sharpen the startup of the music sound output waveform without increasing the loop gain K, a music sound output waveform can be output at a constant level, and the output amplitude can be stabilized. |
