What a bass boost actually does
It raises everything below a corner frequency — here 120 Hz — by a fixed number of decibels, leaving the rest of the song alone. That is a low shelf, and it is what the bass control on an amplifier has always been. Six decibels is a noticeable lift; twelve is a lot, and is where most tracks start to complain.
What it cannot do is invent low end that was never recorded. A track mixed thin gets louder in the bass, not deeper — there has to be something at 60 Hz for boosting 60 Hz to help.
Why boosted bass usually distorts, and why this does not
Modern masters are already close to the ceiling. Add nine decibels underneath one and the peaks go straight past full scale, which is a hard clip: the tops of the waves are cut flat and the result crackles. That is why so many "bass booster" results sound broken rather than heavy.
So the whole signal is pulled down by a little less than the boost before it goes out. The bass is louder relative to everything else — which is what you asked for — without the total ever exceeding what the file can hold. Turn the result up on your own player and it is louder and clean, rather than loud and crunchy.
How much to use
Start around six decibels and listen on whatever you will actually use. Phone speakers reproduce almost nothing below 500 Hz, so a boost that is perfect in headphones may be inaudible there and vice versa — which is an argument for making one version per pair of ears rather than one for both.
If it sounds boomy rather than deep, the boost is too broad rather than too large. There is a full ten-band equaliser on this site for shaping a specific range; this page is deliberately one knob.
Frequently asked questions
How many decibels should I add?
Six is a clear lift and safe on almost anything. Nine is heavy. Twelve is a special effect — usable, but expect the rest of the mix to feel quieter, because it is.
Why does the whole track sound quieter afterwards?
Deliberately. Boosting the bass without lowering everything else would push the peaks past full scale and clip. Turning the result up on your own player gets you the loudness back, cleanly.
It did not get much deeper. Why?
Because there was not much down there to raise. A boost amplifies what exists; if the recording has nothing below 60 Hz, no amount of shelf will create it.
Will this damage my speakers?
The file cannot exceed full scale, so nothing unusual is being sent. Playing heavily boosted bass loudly on small speakers is hard on them, but that is a volume decision rather than something this file does.
Is the file uploaded to boost it?
No. The filter runs in your browser, on your device, and the song never leaves it.
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