What does it mean?
Reverb decay differs from compressor release. In Rigs, the reverb Decay control uses a 0–10 scale; its value does not directly indicate RT60 in seconds.
ExampleHigher Hall Decay gives a longer tail; synth Decay shapes a particular voice's envelope.
How the meaning changes between controls
Reverb
Controls the reverb tail's duration character on a 0–10 scale; the number is not an RT60 value in seconds.
Guitar Synth
The decay part of a particular voice's envelope; the label depends on the selected model.