An envelope is just a CV shape: it can modulate any patchable parameter, not only amplitude

While the most common use of an envelope is controlling a VCA to shape amplitude dynamics, an envelope generator outputs control voltage — a signal that can be routed to any CV input in the system. This means envelopes can modulate filter cutoff (timbral movement over a note), oscillator pitch (portamento-like contours, kick drum pitch sweeps), wavefolder depth, reverb send level, or any other parameter with a CV input. The conceptual shift is from ‘envelope = volume shape’ to ‘envelope = any time-varying CV shape.’ This generalisation is central to advanced synthesis: the same ADSR module that opens the filter of a pad can sweep the pitch of a kick drum or control the rate of an LFO.

Examples

ADSR envelope modulating oscillator pitch: fast attack (0 ms), 80 ms decay to zero = a pitched thump at the start of each note — the classic analogue kick drum pitch envelope. Same ADSR modulating reverb send: the note’s tail adds room ambience after the note ends.

Assessment

Name three synthesis parameters (other than VCA amplitude) that can be usefully modulated by an envelope; for each, describe what the result sounds like with a short fast decay versus a long slow decay.