BMC 75. Envelope Follower

picture of the module

This module converts an audio input to a control voltage output with the control voltage corresponding to the amplitude of the input signal known as an envelope. Most envelope follower designs use a rectifier followed by a low-pass filter, this design uses a track and hold circuit to capture the envelope quickly and accurately. Filtering of the signal can be applied by using the “Smooth” control, this is especially helpful when used with harmonically complex signals like cymbals

This module is compatable with 12V or 15V systems and uses PCB mounted pots.

Boards are available now. Price for 1 PCB is $8.
Unfinished eurorack panels are available for this project, they are 6HP and cost $8 each. There is more information here about panels. If you're interested in drilling your own panel for this project, feel free to use my drill guide. That image should be printed at 300dpi for proper scaling.