Mixing
Compression Explained Simply (Threshold, Ratio, Attack, Release)
A compressor is an automatic volume hand: when a sound gets louder than a line you set, it pulls the fader down. That's the whole machine — the four knobs just define how.
The four knobs, translated
- Threshold — the loudness line. Only what crosses it gets compressed.
- Ratio — how hard it pulls. 2:1 gentle, 4:1 firm, 8:1+ is squashing.
- Attack — how fast it grabs. Slow attack (20–40 ms) lets the transient punch through first; fast attack clamps it.
- Release — how fast it lets go. Time it so the compressor “breathes” with the groove.
Starting points that work
- Vocals: 3:1, medium attack, ~3–6 dB reduction — evens the performance.
- Drum bus: 4:1, slow attack, fast release, 2–4 dB — punch and glue.
- 808: often none (it's already steady) or gentle 2:1 to tame note jumps.
- Master: 1.5–2:1, 1–2 dB max. If the master compressor is working hard, the mix isn't done.
The two classic mistakes
Compressing to sound loud — that's a limiter's job at the end; heavy compression just kills punch. Fast attack everywhere — clamping every transient is why mixes turn lifeless. When in doubt: slower attack, less ratio.
Hear it in context: open a finished FL Studio project file and click through the mixer — real settings teach faster than any article.
Study real mixer chains →Open full FLPs and see every compressor setting — member downloads.Frequently asked questions
What does a compressor actually do?
It automatically turns down audio that crosses a loudness threshold, evening out dynamics — like a fast hand on the fader.
What attack and release should I use on drums?
Slow attack (20–40 ms) so transients punch through, fast release timed to the groove. On a drum bus, 2–4 dB of reduction at 4:1 is plenty.
Why does my mix sound squashed?
Too much ratio and too-fast attack on too many tracks. Compress less, let transients live, and leave loudness to the limiter at the end.