Most notes and other sound events start from silence, get louder until they reach a maximum volume, and then “decay” back into silence. This is sometimes referred to as the “loudness envelope” of a sound. The device in a modular synthesizer that helps perform this function is an “envelope generator” – it can be patched to an amplifier to change the loudness of a sound, as well as other modules such as a filter to change its tone over time. In this video, Chris Meyer explores the most common types of envelope generators.
The concept of “loudness control” is introduced on page 19 of Patch & Tweak, followed by an explanation of envelope generators on page 20; a wide assortment of envelope generator modules are presented starting on page 220. Get your own copy of PATCH & TWEAK here.