A Crest Factor is a measure of the dynamic range of an audio signal.

It is the ratio between the peak level (the highest point of the wave) and the RMS level (the average energy level) of a signal. It is usually expressed in decibels (dB).

• High Crest Factor: High and sharp waves with a lot of calm between them. In audio, this corresponds to a very dynamic sound, with strong transients and a lower body, like an uncompressed drum kit.

• Low Crest Factor: "Flat" and constant waves, almost without peaks. In audio, this corresponds to a dense sound with little dynamic range, like a square wave or an audio signal that has been heavily compressed or limited. Numerical Examples Square Wave: Has a crest factor of 0 dB, as its peak level and RMS level are identical. Sine Wave: Has a crest factor of 3 dB. Compressed Pop Music: Generally has a low crest factor (e.g., 8 dB). Dynamic Orchestral Recording: Has a high crest factor (e.g., 18 dB or more).