A ring modulator multiplies audio by a modulation signal. This is a type of amplitude modulation synthesis. Unlike FM synthesis, which changes the pitch of the oscillator, a ring modulator changes the volume rapidly to add harmonics. This ring modulator comes with several extra controls beyond a normal ring modulator that make it more musical - namely, being able to track the pitch of the modulator along with your oscillator’s pitch. This will give you a more consistent sound across octaves.