A dynamics processor that reduces the volume of signals above a set threshold, evening out the loudness range of a track or mix.
A compressor is a dynamics processor that automatically turns down audio signals that exceed a defined threshold level, reducing the gap between the loudest and quietest parts of a sound. The amount of reduction is set by the ratio, while attack and release controls determine how quickly the compressor responds to and recovers from loud transients.
Why it matters
Compression is foundational to how modern dance music is mastered: it adds punch to kick drums, glues individual elements together, and controls peaks so a mix sits consistently in the speakers without jumping in level. Understanding compression helps DJs evaluate track quality, use sidechain ducking creatively, and avoid clipping when boosting gain.
In practice
When previewing tracks, a very heavily compressed master will sound loud but flat, with little dynamic movement. Tracks with more dynamic range give you more headroom to work with at the mixer; lean on your channel gain rather than the output limiter to compensate for level differences between heavily and lightly compressed tracks.
