ring modulator

A ring modulator is an effect that multiplies the guitar signal with a second signal, usually from an internal oscillator, producing new frequencies that are the sum and difference of the two inputs¹². The carrier signal is typically a sine wave that is not heard on its own³. The resulting overtones are inharmonic, giving a bell-like, ringing quality that can sound metallic and robotic³⁴. Most guitar ring modulators keep part of the original input intact so the output retains some of the signal's musical intent and dynamics⁵. First introduced in the 1930s in telephone circuits, the effect was adopted by synthesizers in the early 1970s⁶.