Envelopes

Envelopes are a critical factor in sound and the production of synthesized music, and they basically control how a sound is produced. The different parameters of envelopes are known as Attack, Decay, Sustain, and Release (ADSR). Attack controls how slow or fast a note takes to reach its maximum volume. Decay controls how slow or fast it takes a note to level down to its sustain volume. Sustain is just the level at which the notes holds steady, and finally Release handles how slow or fast it takes a note to decline back to zero volume level. These are the main sections of envelopes. They are typically applied to filters, volume or in some cases both.