Decay and sustain
What happens while a key is held.
Lesson 2 of 2
Between the attack and the release, two more stages shape a held note. These notes are held for half a bar each.
Held notes
Set Sustain to zero, then change Decay.
Drag the squares on the envelope, or turn the knobs: they move together.
Decay400 ms
Sustain30%
Decay is how quickly the volume falls after the attack.
Sustain is the level it falls to and holds for as long as the key is down. It is a level, not a time. At full sustain the note stays loud like an organ; at zero it dies away like a piano or a pluck, however long you hold it.
Together these four stages are called ADSR: attack, decay, sustain, release. Almost every synth has them, and you have now heard each one.