Audio Equalizer

What the Audio Equalizer Does

The Audio Equalizer reshapes the tone of any audio file your browser can play using a six-band graphic EQ. You load a track, move the sliders for each frequency band, hear the change as it plays, and export the result as an uncompressed 16-bit WAV file. Every step, including decoding, filtering, and encoding, runs locally with the Web Audio API. Nothing is uploaded and nothing is stored.

Six well-placed bands cover the full musical range without overwhelming you with options. That makes the tool useful for quick fixes: adding weight to a thin podcast voice, taming harsh cymbals, pulling mud out of a room recording, or checking how a mix translates with exaggerated bass or treble.

The Six Frequency Bands

How to Use the Equalizer

1. Drop an audio file onto the upload area, click it to browse, or press Load sample sound to try the tool with a built-in demo track.
2. Play the track. Playback is routed through the filter chain, so the sound changes live as you move sliders.
3. Adjust the six bands, or start from a preset such as Bass Boost, Treble Boost, Vocal, or Rock.
4. Wait a moment while the equalized audio is re-rendered, then preview it and press Download WAV.

Each band moves between -12 dB and +12 dB in 1 dB steps. Small moves of 2 to 4 dB are usually enough for corrective work; larger boosts are better saved for creative effects. Press Reset to return every band to flat.

What the Presets Do

• Flat leaves every band at 0 dB, which is the untouched decoded audio.
• Bass Boost lifts 60 Hz and 170 Hz for more low-end weight.
• Treble Boost lifts 3.5 kHz and 10 kHz for extra brightness and detail.
• Vocal cuts a little low end and pushes the 350 Hz to 3.5 kHz range where speech lives.
• Rock combines a bass lift with a slight mid scoop, the classic smile curve.

How the Filtering Works

Each band is a biquad filter, a small recursive digital filter that boosts or cuts a frequency region. The first band is a low shelf that raises or lowers everything below 60 Hz, the last is a high shelf that shapes everything above 10 kHz, and the four middle bands are peaking filters with a Q of 1, which gives each one a moderate, musical width. Shelf and peaking filters do not change the overall loudness of the file, so boosting one range makes it sit forward relative to the rest.

Gains are specified in decibels, a logarithmic scale. A gain of $g$ dB multiplies the signal amplitude of that band by a factor of:

\[ A = 10^{g/20} \]

So +6 dB roughly doubles the amplitude in that range ($10^{6/20} \approx 2.0$), while -6 dB roughly halves it. Keeping boosts moderate avoids clipping, and the tool clamps every output sample to the valid 16-bit range when writing the WAV.

Live Preview and Offline Render

The preview you hear while playing uses a real-time audio graph built from the same filter settings. When you stop moving sliders, the tool renders the track again through an offline audio context, which processes faster than real time and produces exactly the audio you hear, sample for sample. That rendered buffer is what gets encoded to WAV, so the download always matches the preview.

Privacy and Offline Use

Your audio never leaves your device. There is no upload, no account, and no server-side processing. Once the page has loaded, the equalizer keeps working without a network connection, which makes it safe for unreleased music, interview recordings, and any audio covered by confidentiality.

Related Audio Tools

• Audio to WAV Converter converts MP3, OGG, and other formats to WAV without touching the tone.
• Audio Splitter cuts a recording into shorter segments.
• MP3 Reverser plays a track backwards and exports the result.
• Audio Extractor pulls the audio track out of a video file before equalizing it.
• Audio File Size Calculator estimates how large the exported WAV will be.