Ring modulation is a sound synthesis technique in which two high-frequency (periodic) signals are multiplied. This creates a signal that consists of the sum and the difference of the frequencies of both signals, the sum tone and the difference tone. This composite tone, also called multiphonic, often results in disharmonical sounds, which may seem aliasing. Actually, ring modulation is similar to amplitude modulation, except that the original frequencies are no longer found in the modulated signal.
A ring modulator is often present on a synthesizer.
When either input signal is low frequency (below audible range), it is preferable to float, resembling tremolo. Also see
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