the pittsburgh modular adsr is a four stage envelope generator with independently adjustable attack, decay, sustain, and release stages. an envelope generator is used to shape control voltages such as the
gate of the midi module or a square wave from the lfo2.
a pot - attack stage control
d pot - decy stage control
s pot - sustain stage control
r pot - release stage control
i jack - input jack
range switch - adjust the range of the stage controls.
o jack - output jack