LFO effect on harmonic spectrum

Displaying how Pitch LFO begins to create new harmonics after a certain speed.

Tipically, a pitch LFO will make a spring-like effect on the sound wave, meaning it will cycle shorter and longer alternately.

However, when the speed of the pitch modulation becomes faster than the cycling speed of the oscilator itself, then it will begin to make small stretches inside the basic wave shape, meaning that you dont hear pitch fluctuations anymore, instead, the sound generation becomes different, with new harmonics coming from the oscilator's change of shape.

This is the same that happens during FM Synthesis, with the difference that FM Synths have modulation waves that are key tracked, meaning they changes its pitch along with the oscilator played key, while in a LFO the speed of the modulating is fixed no matter which key you play.