A ring modulator is a module that processes two input signals (usually called “carrier” and “modulator”) to generate a complex output signal. It does so by multiplying the amplitude (or level) of the two input signals together, creating an output signal that consists of the sum and difference of the input signals’ frequencies.
Ring modulators are used in modular synthesizers for various purposes, such as:
- Sound design: Ring modulation can produce a wide range of harmonic-rich and inharmonic sounds, from metallic and bell-like tones to aggressive and dissonant textures. This makes it an excellent tool for creating unique timbres and sound effects.
- Frequency modulation: When audio-rate signals are used as both carrier and modulator, ring modulation can act as a form of frequency modulation (FM), generating complex sidebands that result in a rich harmonic spectrum.
- Amplitude modulation: When one of the inputs is a low-frequency signal (such as an LFO or envelope), ring modulation can serve as a form of amplitude modulation (AM), controlling the amplitude of the audio signal in a dynamic way.