Modulator

We touched on the general subject of modulation and modulators in the definition above. However, quite often when someone uses the term modulator, they’re usually discussing a synthesis techniques where one usually audio-rate signal “modulates” (varies) another audio signal. For example, in frequency modulation (FM) synthesis, the modulator (or modulating oscillator) varies the frequency (pitch) of the main signal generator (oscillator), called the carrier. In ring, balanced, or amplitude modulation, the modulator is varying the loudness of the carrier signal. So the term modulator is a way to make it clear which component you’re talking about in one of these patches: not the main tone generator, but the module that is driving that generator crazy.