Limiter gain reduction shows how hard the final peak controller is working.
Definition
The level the limiter removes
Limiter gain reduction is the amount of level pulled down when peaks try to exceed the limiter threshold or ceiling. More gain reduction usually means more loudness pressure.
A limiter can reduce brief peaks cleanly, but constant reduction changes groove, density, and transient shape.
Risk
The number is context dependent
One decibel of reduction on a dense chorus may be inaudible, while the same amount on a sparse acoustic track can feel obvious. The meter is a warning, not a universal limit.
Fast, repeated gain reduction often points to pumping, dull transients, or distortion before the true-peak ceiling ever looks unsafe.
Practice
Read gain reduction with loudness
Watch limiter reduction while checking integrated loudness and true peak. If more drive adds little loudness but much more reduction, the limiter is past its useful range.
Use level-matched comparisons to decide whether the extra density helps the song or only makes the meter look louder.