ADSR refers to four common controls that come with virtual instruments and synthesizers. Adjusting these shape the sound and give it a different feel. The “A” stands for attack. The attack is the time it takes for the note to reach the maximum level of volume. A slow attack creates a smooth swell, while short attack will create more of a pluck. “D” stands for decay. This is the time it takes for the note to go from the maximum level to the sustain level, which comes next in the chain. Sustain refers to the level of volume over the time the note is held on the keyboard. Lastly, release is how long the note lasts after the key is let go.
- Envelope containing the basic ADSR parameters
Music Production - All You Need To Know 