Distortion

Any change to a waveform's shape that adds harmonics not present in the original, and in guitar terms the deliberate overdrive that defines amplified electric tone.

Clipping happens when a circuit runs out of headroom, whether that is a valve, a transistor, a diode or a converter. Hard clipping cuts the waveform into a shape with abrupt corners and produces strong odd harmonics, heard as a biting, aggressive sound; soft, rounded clipping produces more even harmonics and a warmer, smoother result. Because the character depends on where in the chain clipping occurs, an amp's own distortion sounds different from a pedal doing the same job.

Example: pushing a valve amplifier into output clipping adds compression that sustains notes, where a hard-clipping pedal at the same level keeps a drier, sharper edge.

Distortion

See also