Kazuhisa Okamura

Method and apparatus for synthesizing music tones with high harmonic content

A musical tone signal is synthesized on the basis of a predetermined modulation operation (e.g. an FM or AM operation) employing a modulating signal and a carrier signal respectively having an audio range frequency. The modulating wave signal and/or carrier signal is derived by reading out a predetermined waveshape signal from a waveshape table in accordance with progressive phase angle data. The value of the waveshape signal read out from the waveshape table is modified in a specified phase section. This modification is effected by applying a simple operation such as gating, shifting or selecting to the phase angle data addressing the waveshape table or to the waveshape signal read out from the waveshape table. The modified waveshape signal is utilized in a predetermined modulation operation as the modulating wave signal and/or carrier signal. The frequency component of the modulating signal and/or carrier signal is controlled by the waveshape modification wherby synthesis of a musical tone having abundant frequency components is realized with a simple circuit construction.