Eurorack Dual AR Envelope Project

This is my Eurorack Dual AR Envelope. It takes a trigger/gate in and outputs a simple AR contour. It's not the snappiest attack in the west, but it gets the job done. My objective was to take a simple, cost-effective circuit that could fit on a 6HP panel. I wanted to build the Nonlinearcircuits Triad design, which has three AR envelopes, but did not want to do any SMT soldering. So I opted to layout my own through-hole PCB. I like their circuit for the simplicity, and it uses only easy-to-source parts that I already had on hand. The link to my adaptation of their design is HERE. I have included front panel, hole locations, and the original schematics for reference. I substituted BC547 NPN transistors on mine and they work fine. I measured current consumption at 25mA on +12v, 23mA on -12v, 5v is not used. I am not affiliated with Nonlinearcircuits.