Audio Frequency is the range of frequencies that the human ear is able to perceive.

This range is measured in Hertz (Hz) and, by convention, goes from 20 Hz to 20,000 Hz (or 20 kHz).

• Low Frequencies (Bass): These correspond to low-pitched sounds, such as the bass drum of a drum kit or the low notes of a double bass (e.g., 20 Hz to 250 Hz).

• Mid Frequencies: Where most of the information of the human voice and melodic instruments is found (e.g., 250 Hz to 4 kHz).

• High Frequencies (Treble): These correspond to high-pitched and bright sounds, such as the cymbals of a drum or the hiss of the voice (e.g., 4 kHz to 20 kHz).

Any sound we hear is composed of one or more frequencies within this spectrum.