Bass Booster

Start with a small boost first. If the kick, bassline, or vocals become muddy, lower the bass amount and preview again.

What Does Bass Boost Do?

Bass boost raises the level of the low-frequency content already in a recording. It does not add bass that was never there — if a track has no energy below 60 Hz, no amount of boosting will invent any. What it does is change the balance, so the parts of the mix that live low down (kick fundamentals, basslines, 808s, the body of a low voice) sit further forward relative to everything else.

The shape of that lift matters as much as the amount. This tool uses a low shelf with its corner at 150 Hz: everything below the corner is raised by roughly the amount you set, with a transition band around it, and the region well above is left where it was. That is different from a bell or peak filter, which picks out one band and leaves the frequencies on either side of it alone. A shelf is the right shape for “more weight underneath the whole track”; a bell is the right shape for “this one boomy note needs taming”. Because a shelf raises the entire bottom together, the effect is broad and even, but it also means a big boost reaches up into the lower vocal range rather than staying politely below it.

Why Bass Boost Clips, and How Much Your Track Can Take

Boosting is addition, not redistribution. A +6 dB shelf doubles the amplitude of everything under the corner, and that has to fit somewhere. Digital audio has a hard ceiling at 0 dBFS, so the only thing that decides how much boost a file can absorb is how much room is left between its current peak and that ceiling. That gap is called headroom, and it is the number that actually governs the outcome — not the genre, not the slider position.

This is why the same +8 dB can sound enormous on one track and like crackling mush on another. A quiet, dynamic recording peaking at −12 dBFS has room to spare. A modern master pushed to −0.3 dBFS has essentially none, and the boosted low end gets flattened against the ceiling the moment the kick lands. Neither result is the tool misbehaving; they are the same operation applied to files in very different states.

You do not have to guess at that number. Run the file through the volume booster, which reports sample peak, true peak, integrated loudness, and remaining headroom before it changes anything. Read the headroom figure, then come back and treat it as your budget: if the file has 3 dB left, a +3 dB shelf is roughly the point where the loudest bass moments start hitting the ceiling. If it reports almost no headroom, reduce the overall level first and boost afterwards — the order matters, because there is nothing to be gained by boosting into a wall and then turning the clipped result down.

One caveat on true peak specifically: a file can show a sample peak below 0 dBFS and still overshoot once a DAC or a lossy decoder reconstructs the waveform between samples. If you are exporting MP3, leave a little more margin than the sample-peak number alone suggests.

Related edits: change timing with the audio speed changer, move the key with the pitch shifter, or build a slowed atmospheric edit with the slowed reverb generator.

Bass Booster Online FAQ