IADSR [Initial/Attack/Decay/Sustain/Release]

This is an Attack/Decay/Sustain/Release (ADSR) envelope generator that allows you to start the attack phase at an initial level – the “I” – rather than the customary 0 volts. The envelopes in the Prophet VS, as well as a module from Ladik, have this capability; IMHO more should adopt it.