yes but an adsr is a very specific envelope...
they are usually used for keyboards - not necessarily something that you always need in a modular synth - a lot of people just use AD envelopes - or more complex ones, like from zadar...
"some of the best base-level info to remember can be found in Jim's sigfile" @Lugia
Utility modules are the dull polish that makes the shiny modules actually shine!!!
sound sources < sound modifiers < modulation sources < utilities