The Befaco VC ADSR is an envelope module for modular synthesizers in Eurorack format. The module can be triggered either via gate or trigger signals. A switch can be used to determine if the module responds to Trigger or Switch, and the individual steps of any envelope can be modulated either manually or by CV. The times of the individual steps are between 3ms and 20 seconds for attack, between 2.8ms and 10 seconds for decay and between 2.8ms and 10 seconds for release. In the event that negative CV voltages are used, the minimum can drop to 200 microseconds for attack and 400 microseconds for decay.