| 摘要 |
PURPOSE:To enable a user to enjoy various effect sounds with ease with an acoustic apparatus, such as electronic musical instrument, by imparting the effect corresponding to arbitrary waveforms to sound signals in accordance with the operation to draw the arbitrary waveforms. CONSTITUTION:The value of MP changes in accordance with the amplitude change of the waveform W if the waveform as shown by W is drawn with respect to a reference line RL by an electronic pen 24 on an operation panel 22. The value of the output data AD of an adder circuit 16 changes in accordance with the amplitude change of the waveform W around the value of pitch code data PC. The frequency of the musical tone signal TS generated from a sound source circuit 18 at this time, therefore, changes in accordance with the amplitude change of the waveform W and the vibrato effect consisting of the waveform W as a modulating wave is obtd. The change width of the pitch is larger as the amplitude change of the waveform W is larger and the changing speed of the pitch is higher as the speed to draw the waveform W is higher. |
