ADSR Envelope Generator
Attack-Decay-Sustain-Release envelope generator, an expansion on Ray Wilson’s Music From Outer Space design.
This module is used to generate a contour control voltage in a synthesiser. It’s what helps make a sound snappy, or makes it smoothly fade in and out. It can be used in combination with a lot of components, but that is the general idea.
I wrote an extensive write-up about the original circuit and my additions to it, fully detailing how the whole thing works; this can be found over on synth.michd.me.
The circuit design is based on Ray Wilson’s ADSR design, with these additions:
- LEDs in the sliding potentiometers indicate which stage the generator is in
- Option to retrigger itself when the decay stage ends, which essentially turns it into an oscillator
- End-of-decay trigger output
- Additional timing range
The panel contains two of the boards on the back, as seen here:
- Additional circuit design / prototyping on breadboard
- Schematic capture (KiCad)
- Circuit board design (my first one involving surface mount technology) (KiCad)
- Front panel design (Inkscape)
- Laser cutting, on local makerspace’s laser cutter
- PCB assembly (reflow oven, and through-hole soldering)
- Panel assembly