What is an envelope?
What is an envelope?
Envelope (VCA): The shape of a sound in relation to time. The attack is the start or onset of the initial transient sound. Decay is the roll-off of the sound's waveform just after the peak of the initial attack. Sustain is the length of time the sound lasts while a key is held down. Release is length of time for the sound to end after the key is released. Some examples: A snare drum is mostly attack with very little decay and almost no sustain or release time. A strummed open string on a guitar has a quick attack and delay with a very long sustain and release time.