Vibrato is an effect that creates a subtle or pronounced pitch variation by modulating the signal up and down over time. Unlike chorus or tremolo, vibrato affects pitch only, producing a wavering or shimmering sound without changing volume.

It is used to add movement, expression, and a sense of warmth to a sound, working especially well on sustained notes and chords. Vibrato can range from gentle and musical to bold and psychedelic, and is commonly found in vintage amplifiers, modulation pedals, and classic studio effects.