How to equalize audio
- Drop your audio file into the box or choose it. Several files at once work too.
- Pick a Preset such as Bass boost or Clear speech, then fine-tune the bands: drag a slider or type a value from −12 to +12 dB.
- Play the result next to the original. It updates when you change a setting; download it when it sounds right.
How the equalizer works
Each band is a peaking filter, the standard building block of graphic and parametric equalizers, using the formulas from Robert Bristow-Johnson’s Audio EQ Cookbook. A filter centred on 1 kHz with +4 dB raises the sound around 1 kHz by up to 4 dB and leaves frequencies further away untouched, with a smooth slope in between. The bands are about 1.25 octaves wide, so neighbouring bands overlap and moving two of them together gives a smooth, broad change rather than a narrow peak.
The whole file is processed at once rather than live, so the result you hear in the player is exactly the file you download.
Getting a good result
- Small moves first: 3 to 6 dB is a clearly audible change. Large boosts quickly sound unnatural and use up headroom.
- Cut rather than boost: if a recording sounds muddy, lowering 150 Hz and 400 Hz often helps more than raising the treble.
- Compare at the same loudness: a louder version usually sounds better at first, so judge the tone, not the volume.
- Clean up speech: for voice recordings, try Clear speech, then normalize audio to bring the level up.
For a bigger bass boost with simple settings, use bass booster. To take the vocals out of a song, try vocal remover.