What Is an Equalizer (EQ)?
Updated October 2026
An equalizer, or EQ, changes the balance of frequencies in a sound. It can boost or cut a band, so a voice can be made warmer, clearer or less harsh.
The short version
- EQ boosts or cuts bands of frequency: low, low mid, presence and high.
- Cut what you do not like before you boost what you do like.
- Make small changes, 1 to 3 dB, and listen at normal volume.
- EQ shapes a sound; it cannot add detail that was never recorded.
The short definition
An equaliser changes the level of part of the frequency range. A band can be boosted to add emphasis or cut to reduce it. The bands are often named low, low mid, mid, presence and high, and most equalisers can set the centre frequency, the width of the band and the amount.
What each part does to a voice
- Low (below about 150 Hz): body and rumble. Cut the rumble, boost gently for warmth.
- Low mid (about 150 to 500 Hz): fullness, and sometimes muddiness.
- Presence (about 2 to 5 kHz): clarity and the words. A small lift helps a muffled voice.
- High (above about 8 kHz): air and sheen, and also sibilance.
Use it gently
Cut before you boost. A small cut in a problem area often does more than a large boost elsewhere. Change one band at a time and listen at normal volume, because a boost that sounds bright quietly can sound harsh when louder.
What EQ cannot do
EQ changes what is there. It cannot restore frequencies the microphone never captured. A very dull recording needs a better take, not a bigger boost. For a muffled voice, see the muffled voice guide.
Shape the voice without the harshness
Tunedzy’s tone step shapes a voice toward a clear, even sound. Use Before and After to check the result.
Free tools for this
Frequently asked questions
Should I boost or cut first?
Cut first. Removing a problem is usually cleaner than adding a boost to hide it.
How much EQ is too much?
If the voice sounds unnatural, or the change is loud when you compare it, it is too much. Small moves are usually enough.
Is a graphic EQ or a parametric EQ better?
A parametric EQ lets you set each band precisely, which suits voice work. A graphic EQ is simpler for quick moves.
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