ELECTRONIC MUSICAL INSTRUMENT

摘要

There is described a tone generator in which waveform amplitude data is generated from a table of sinusoid values in an addressable memory by changing the addresses as a function of time in a periodic or sinusoidal manner. The effect is to produce a sequence of sinusoidal values from the table which correspond to a series of points on a frequency modulated carrier signal. By making the effective modulation frequency equal to the carrier frequency, the resulting frequency modulated signal corresponds to a carrier with side bands that correspond to harmonics of the carrier. The relative amplitudes of these harmonics can be varied as a function of time to produce the sliding formant effect of a synthesizer.