| 摘要 |
PURPOSE: To generate a sound of a desired tone by rewriting each memory data in a device by providing a memory storing a waveform and a shape of an envelope in a sound source. CONSTITUTION: A oscillation circuit 1 is constituted with a CR oscillation circuit, a crystal oscillation circuit, or an oscillation circuit of a ceramic vibrator, oscillates an objective frequency, and inputs a signal having a oscillation frequency to sound sources 3-5 and a rhythm sound generation circuit 6. And the circuit 1 inputs a signal having a frequency to which an oscillation frequency is divided by 1/M to a control circuit and a rhythm sound generation circuit 6. And the circuit 1 mixes analog voltage of sound from plural sound sources and analog voltage of a rhythm sound in a mixer circuit 7 and generates analog voltage of a sound output finally. A sine wave, rectangular wave and sawtooth wave are stored in a waveform ROM 61 of three sound sources 3-6, and a trapezoidal wave shape and triangle wave shape are stored in an envelope ROM 55. Thereby, various tones can be generated by storing waveforms and envelopes of the sounds of musical instruments in the ROM 61 and ROM 55. |
