What does it mean?
A compressor or limiter restores gain; a gate closes; Auto Swell lowers its fade; a synth releases its envelope. Release is not a direct instrument-sustain control.
ExampleA longer gate release helps a note's ending fade more smoothly.
How the meaning changes between controls
Compressor
How quickly gain recovers as level falls.
Noise Gate
How quickly the gate closes when input becomes quiet again.
Auto Swell
How quickly the fade or envelope falls to release the current swell or prepare for the next one.
Guitar Synth
The voice's release or decay envelope; some models use the label Decay.
Limiter
How quickly the limiter's gain recovers after a peak.