Squeeze the dynamics — and watch exactly how hard you're squeezing.
Drop a file, set threshold and ratio, and the meter shows the gain reduction as it happens, so you hear the squash and see it at once. Attack and release shape the movement, makeup gain puts the level back. Export a WAV.
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Gain reduction measured on the rendered signal (30 ms blocks): block RMS of your dry file against block RMS of the compressed render, with the makeup gain divided back out. The bar moves because the measurement moves.
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Two starting points, and what the numbers are really doing
A drum bus and a vocal want opposite treatment. On a drum bus, a slower attack (around 20 ms) lets the initial hit of each kick and snare through untouched, then clamps the body that follows — that is the glue that makes a kit sound like one instrument. Moderate ratio, modest reduction, and the meter should be dancing on the peaks rather than sitting pinned. On a vocal, go lower on the threshold and gentler on the ratio, with a short attack to catch the stray peaks and a longer release so the level breathes instead of pumping between words. If you can hear the compressor working as a rhythmic movement, the release is too short for the material.
Makeup gain is not an undo button. Compression lowers your loud parts, so the file comes out quieter than it went in; makeup gain is clean gain added after the fact to put that level back. The dynamics stay compressed either way — you are recovering headroom you already spent, not cancelling the reduction. Set the compression first with makeup at zero, listen, then bring the level back up and watch the peak guard line tell you where you stand.
One honest note: a compressor narrows dynamics. It is not a mastering chain, and it cannot fix a noisy room, a clipped take or a badly placed mic — those problems just get louder and more even. Heavy ratios smear the transients that give a track its punch, so if you need more than a few dB of steady reduction, the fix is upstream in the recording, not further down in this panel.
Frequently asked questions
What do threshold, ratio, attack and release actually do?
Threshold is the level above which compression starts working. Ratio says how hard it works: 4:1 means every 4 dB above the threshold comes out as 1 dB. Attack is how quickly the compressor clamps down once the signal crosses the threshold, and release is how quickly it lets go again. Short attacks catch transients, longer ones let the initial hit through.
Why does the gain-reduction meter matter more than the settings?
The numbers are a starting point; gain reduction is what you actually hear. Two files with identical settings can be compressed very differently, because the amount of reduction depends on how loud the material already is. Watching the meter tells you whether you are shaving 3 dB off the peaks or crushing 12 dB out of the whole performance.
What is makeup gain for?
Compression lowers the loud parts, so the result gets quieter. Makeup gain is a clean boost applied after the compressor to bring the level back up to where it was, or wherever you want it. It does not undo the compression; it just recovers the headroom you spent.
Will compression fix a bad recording?
No. Compression evens out dynamics within a performance, it cannot repair noise, clipping, bad room sound or a badly placed mic. It is also easy to overdo: a heavy ratio on an already-mastered mix makes the loud parts pump and smears the transients that give the track its punch. If it needs more than a few dB of reduction, the problem is upstream.