Bass Booster
Add low-end weight with a shelf and a mud cut, not a blunt volume bump
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Interactive Workspace
Bass Booster
A bass boost is easy to get wrong. Raising low frequencies also raises the range where boom and mud live, so a naive boost makes a track sound louder and worse at the same time. This tool pairs a low-shelf boost with a low-mid cut so the added weight stays defined.
How the two controls work together: the shelf raises everything below the chosen corner frequency — the fundamental weight of kick drums and bass lines. The low-mid cut trims the 200–500 Hz region, which is where boxiness accumulates. Reducing it makes the boost sound tighter, not quieter.
Choosing a corner frequency: 80–120 Hz suits most music; it lifts the fundamental without adding rumble. For speech, 120–180 Hz adds chest tone without turning plosives into thumps. Pushing the corner down toward 60 Hz emphasises sub content, which small speakers cannot reproduce anyway.
Watch the headroom: low-frequency energy carries a lot of power, so a +8 dB shelf can easily push the output into clipping. The output trim is there to bring the level back after the boost — use it rather than lowering the boost, because the tonal change is the point.
Export: WAV for further editing, MP3 for listening. Decoding, processing, and encoding all run in this browser tab. The file you select is not uploaded, and the rendered audio is not stored on any server.
How It Works
Load a track
Add the music or recording that needs more low end.
Set the boost
Start around +6 to +8 dB — above that, most material starts to clip.
Tune the corner
Set the shelf frequency, then cut low-mids to clear the mud.
Render and export
Compare with the original, then download WAV or MP3.
Features
Low-shelf Boost
Up to +15 dB below a frequency you choose, from 60 Hz to 240 Hz.
Low-mid Cut
Trims the boxy 200–500 Hz band so the boost stays punchy.
Adjustable Corner
Set the shelf frequency to suit music, speech, or sub content.
Headroom Control
Output trim brings the level back after the boost.
Shelf, Peak, and the Difference It Makes
This tool uses a shelving filter, which raises every frequency below the corner by the same amount. That is the right shape for adding weight: it lifts the whole low end rather than creating a resonant bump at one frequency. A peaking filter at, say, 60 Hz would produce a narrow boost that sounds boomy and unnatural on material whose bass notes do not sit at that exact frequency.
The corner frequency is the parameter worth experimenting with first. Music usually wants 80–120 Hz, because that covers the fundamental of a kick drum and the low end of a bass guitar without reaching into the sub range where most playback systems give up. Speech wants a higher corner, around 150 Hz, and a gentler amount.
Headroom, Playback Systems, and Review
Low frequencies carry more energy per unit of perceived loudness than mid frequencies, so a bass boost raises the true peak faster than the level meter suggests. Reduce the output trim if the processed preview shows the limiter engaging constantly — that is a sign the boost has consumed the headroom the mix had available.
Every effect here is deterministic: the same file and the same control values produce the same output. That means you can reproduce a result later, but it also means the tool will not guess what you intended — check a short excerpt before rendering a long file, and keep the original.
Judge the result on more than one playback system if you can. Headphones flatter a bass boost because they couple directly to the ear; a laptop speaker will not reproduce the same content and may even sound thinner after the low-mid cut. If the material has to work everywhere, aim for a boost that is audible but not dominant on the smallest system you expect people to use.
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Bass Booster — FAQ
How much bass boost is safe?
Around +8 dB is a sensible ceiling for most material. Beyond that, low-frequency energy consumes headroom quickly and the output limiter starts working hard, which flattens dynamics. If +8 dB is not enough, the recording probably lacks bass content rather than needing more gain.
Why cut low-mids when boosting bass?
The 200–500 Hz range is where a mix accumulates boxiness. Boosting below it without trimming that band produces a sound that measures louder but reads as muddy to a listener. Cutting it makes the added low end feel tighter.
Will this work on phone speakers?
Only partially. Phone speakers cannot reproduce much below 200 Hz, so a sub-bass boost is largely inaudible there. The low-mid cut, however, does help on small speakers because it removes energy that masks the midrange.
Can I boost bass on speech?
Yes — use a corner frequency around 120–180 Hz and a modest boost of 3–5 dB. This adds chest tone to a thin voice. Higher amounts start amplifying room rumble and plosives.
Does this change the file permanently?
Only in the copy you download. Your original file on disk is never modified.
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