Bass covers roughly 20 to 250 Hz, mid 250 Hz to 4 kHz and treble 4 to 20 kHz. Bass gives warmth and weight, mid carries the voice and most instruments, and treble adds clarity and air. A 3-band EQ lets you turn each range up or down; small moves of 1 to 3 dB are usually enough.
In Short
The short version:
- Bass: 20–250 Hz. Warmth and weight; too much sounds boomy.
- Mid: 250 Hz–4 kHz. Voices and most instruments; too much sounds boxy or nasal.
- Treble: 4–20 kHz. Clarity and air; too much sounds harsh.
- Cut first, boost second, and keep changes within 1–3 dB.
- Compare with the original at the same loudness before you decide.
What Are the Bass, Mid and Treble Frequency Ranges?
Sound is vibration, and frequency is how many times it vibrates per second, measured in hertz (Hz). Slow vibrations are heard as low notes and fast ones as high notes. The range we can hear is commonly divided into three bands:
- Bass (lows): 20 Hz to 250 Hz
- Mid (midrange): 250 Hz to 4,000 Hz (4 kHz)
- Treble (highs): 4 kHz to 20 kHz
The borders are conventions, not laws: different mixers and apps draw them in slightly different places. What matters is what each range does to the sound, which the chart below shows.
How We Hear Frequencies
A young, healthy ear hears from about 20 Hz to 20,000 Hz, and the upper limit falls with age. Hearing is not equally sensitive across that range: we hear best between roughly 2 and 5 kHz, where the consonants of speech sit, and need much more level to hear deep bass at the same loudness. The hearing tests published by the School of Physics at UNSW Sydney let you check this on your own ears.
This has two practical consequences. A boost of 2 dB at 3 kHz is far more noticeable than the same boost at 80 Hz, so go gently in the upper mids. And what you hear depends on how loud you listen: at low volume, bass and treble seem to fade, so judge your EQ at a normal listening level.
Audio Frequency Chart
Use this chart to put a name to what you hear. When something sounds wrong, find the description that fits and you know where to look.
| Range | Frequencies | What lives there | Too much sounds… |
|---|---|---|---|
| Sub-bass | 20–60 Hz | Felt more than heard: the lowest notes of bass and kick drum | Rumbling; uses up headroom |
| Bass | 60–250 Hz | Warmth and weight of voices, bass and drums | Boomy, muddy |
| Low mids | 250–500 Hz | The body of voices and instruments | Boxy, like a cardboard box |
| Mids | 500 Hz–2 kHz | The core of speech and most melodies | Nasal, honky, like a telephone |
| High mids | 2–4 kHz | Consonants and the attack of instruments | Harsh, tiring |
| Presence | 4–6 kHz | Clarity and definition; S and T sounds | Sharp, sibilant |
| Brilliance and air | 6–20 kHz | Sparkle of cymbals, breath and room | Hissy, brittle |
How to Set a 3-Band EQ
A 3-band EQ gives you one control each for bass, mid and treble. In our 3-Band EQ, each band also has a frequency slider, so you can move it to where the problem is: Bass between 40 and 500 Hz, Mid between 200 Hz and 5 kHz, and Treble between 2 and 16 kHz. Press Preview and change one band at a time.
Bass: Warmth or Mud
Bass gives a voice authority and music its weight. If a voice booms, as it does when you are very close to the microphone, lower Bass by 2 to 3 dB. If music sounds thin, a boost of 1 to 2 dB is usually enough. Avoid boosting the bass of a voice recording: it mostly raises rumble and hum.
Mid: Body or Boxiness
The mids carry what a voice is saying. For a boxy sound, set the Mid frequency to about 300 Hz and cut 2 to 3 dB. For a nasal, telephone-like sound, move it to around 1 kHz and cut 1 to 2 dB. If a voice gets lost under music, cut the mids of the music rather than boosting the voice.
Treble: Clarity or Harshness
Treble makes a recording sound open and clear. If audio sounds muffled, as if under a blanket, raise Treble by 2 to 3 dB. If S sounds become sharp, don’t cut all the treble: a de-esser, such as the one in the Noise Gate & De-Esser, turns down only the harsh moments.
Cut or Boost?
When something sounds wrong, look first for what there is too much of, and turn that down. Cutting keeps the level under control and rarely sounds artificial; boosting raises the overall level and can push the peaks into clipping. Louder also tends to sound “better”, which fools the ear, so after boosting, lower the overall volume to match the original before you compare.
EQ Starting Points for Common Problems
These settings are for a 3-band EQ. Start here and adjust by ear.
| Problem | Bass | Mid | Treble |
|---|---|---|---|
| Boomy voice | -2 to -3 dB | 0 dB | 0 dB |
| Boxy voice | 0 dB | -2 to -3 dB at 300 Hz | 0 dB |
| Dull, muffled voice | 0 dB | 0 dB | +2 to +3 dB |
| Harsh, thin voice | +1 dB | -1 to -2 dB at 3 kHz | -1 dB |
| Music lacks punch | +2 dB | 0 dB | +1 dB |
| Music covers a voice (EQ on the music) | 0 dB | -2 to -4 dB at 2 kHz | 0 dB |
What EQ Cannot Fix
EQ changes the balance of what was recorded; it cannot add what is missing or separate sounds that overlap. Distortion from clipping, room echo and noise under a voice all stay. For those, see how to prevent audio clipping and how to remove background noise; for a complete voice workflow, read How to Make Your Voice Sound Professional.
Train Your Ears
Knowing the chart is one thing; recognizing 300 Hz or 3 kHz when you hear it takes practice. The Ear Training tool plays tones at different frequencies and quizzes you on which one you heard. A few minutes a day makes EQ decisions much faster. The ear training guide explains how to practice.
Try the 3-Band EQ
Open a recording, press Preview and hear what each band does.
Open the 3-Band EQFree, no sign-up, and your files never leave your device.