The Cutoff Frequency is the frequency at which a filter begins to attenuate the signal.

It is the exact point in the spectrum from which the filter begins to cut the volume of the sound.

• In a low-pass filter:All frequencies above the cutoff frequency are attenuated.

• In a high-pass filter:All frequencies below the cutoff frequency are attenuated.

Technically, the cutoff frequency is defined as the point at which the signal has already been attenuated by 3 dB. It is the main control in synthesizer filters, used to shape the timbre, and in equalizers, to remove unwanted frequencies.