Simple Explanation

A tool that adjusts specific parts of the sound—like making the bass louder or reducing harsh treble.

Concise Technical Definition

A circuit or software function that boosts or cuts selected frequency ranges in an audio signal to shape tonal balance.

Layman-Friendly Analogy

Like seasoning food—turning up the bass is like adding more salt, turning down harsh highs is like cutting bitterness.

Industry Usage Summary

EQ is used in mixing, mastering, live sound, and home theater to correct room issues, tailor speaker response, or shape sound creatively. Types include graphic EQs, parametric EQs, shelving filters, and notch filters.

Engineering Shortcut

Frequency-selective gain control—cut or boost specific ranges.

Full Technical Explanation

An equalizer (EQ) is a type of audio filter used to adjust the amplitude of specific frequency components in an audio signal. EQs can be hardware-based or digital (software-based), and come in various forms such as graphic EQs (fixed frequency bands), parametric EQs (adjustable frequency, bandwidth, and gain), shelving filters (affecting all frequencies above or below a point), and notch filters (used to cut narrow frequency bands). EQ is fundamental in audio production and playback for correcting tonal imbalances, compensating for room acoustics, or creatively shaping a sound. It can be applied manually or automatically via DSP systems.