Audio Equalizer Online: Change Five Bands Without Uploading Your Track
A 6 dB cut at 250 Hz changes a mix more than a new export format ever will. That band often contains the body of a guitar, piano, or vocal, along with low-mid buildup. Use the equalizer above to hear the difference before you download anything. Your source file is decoded and processed in your browser. Nothing is sent to our server. Start with a small cut or boost, compare the processed version with the original, then adjust by ear on the speakers or headphones you actually use.
What the five controls do
The 60 Hz control is a low shelf. It raises or lowers bass beneath the selected frequency rather than changing only a single note. A kick drum or sub-bass may respond strongly; a spoken recording with little low-frequency content may barely change. The 250 Hz control is a peaking filter centered on the low mids. If a track sounds boxy, try a cut of 2 or 3 dB there before adding more treble. The 1 kHz band reaches the middle of many instruments. A big cut can make vocals seem distant, even if the waveform peak stays similar.
The 4 kHz control targets upper-mid presence. A small increase can bring consonants forward, but strong boosts can make cymbals or vocals sound sharp. The 12 kHz control is a high shelf that acts on the upper treble. If a recording sounds dull, try a modest increase and check for hiss. The middle three bands use peaking filters with a fixed Q of 1. There is no bandwidth slider. The frequency positions are fixed too, so this is a quick tonal EQ rather than a surgical parametric equalizer. Each band moves from -12 dB to +12 dB in 1 dB steps.
How the browser processes your file
The tool chains five BiquadFilterNode filters in an OfflineAudioContext. The browser renders the full file at its decoded sample rate, then converts the result to a 16-bit PCM WAV. The first and last filters are shelves; the others are peaking filters. The MDN BiquadFilterNode reference documents the filter types and their parameters. The Web Audio specification for offline rendering describes why rendering can complete without playing a file in real time.
The output stays at the browser-decoded sample rate, which may differ from the source file. If the processed samples would exceed 0 dBFS, the tool reduces the entire rendered file until its largest sample is 0.99 in linear amplitude. This prevents clipping in the downloaded WAV, but a large boost followed by that reduction can make other frequency bands quieter than expected. It is not a loudness-matched A/B test. Set the bands back to zero to hear the untouched response; the original preview plays your decoded source, while the processed preview plays the rendered result.
A practical starting point for a muddy mix
Suppose your track has a strong kick and a bass guitar that mask each other. Lower 250 Hz by 3 dB, leave 60 Hz at zero, and listen again. If the bass now feels too thin, try +2 dB at 60 Hz. This is a listening example, not a universal preset. The right choice depends on the recording, arrangement, and playback system. A phone speaker may reproduce little at 60 Hz, while headphones can make the same change obvious. Avoid pushing every slider upward; several boosts can consume headroom even if each one sounds mild alone.
If you need to check a specific note instead of a broad band, our note frequency calculator converts pitches to hertz. For a narrower bass-only adjustment, try the bass boost tool. Need a second opinion on playback level? The loudness meter measures integrated LUFS and peak data on a finished file. It can show changes in level that your ears might mistake for a better EQ curve.
To make a fair comparison, lower your playback device if the processed version is louder. Human hearing often prefers the louder option even when the tonal balance has not improved. Listen to the same verse or chorus several times, then return the sliders to zero and try the opposite direction. A 2 dB cut may solve a problem that a 6 dB boost elsewhere only conceals.
Export format, limits, and hearing checks
You can load a browser-decodable mono or stereo file up to 100 MB, with a decoded-memory limit of 128 MB. WAV, MP3, OGG, AAC, and other formats depend on browser support; a listed extension does not guarantee decoding on every device. Export is always a 16-bit WAV, even if you imported an MP3. Converting a lossy input to WAV cannot restore details already discarded by the original encode. For an estimate of uncompressed output size before working with a long recording, use the sample rate and bit depth calculator.
Make changes at a comfortable monitoring level. A strong treble boost can make a quiet file fatiguing, and a small adjustment on one set of speakers may be excessive on another. Check the result on a second playback device before sharing it. If you want a smaller delivery file, export the WAV here and then use the audio converterto make an MP3. Equalization changes tone, not the file's codec or compression ratio.
