Build Your Own Clone
Add some funk to your pedal board! The BYOC envelope filter kit is based on the DOD440 and features an NOS Vactec VTL5C4/2 opto-coupler. Compared to other envelope filters, this may be a one-trick-pony, but it does it's one trick well.
This is the circuit that gained popularity after Radiohead used it to record, but it's really a must have for any funk or reggae players or anybody who's just looking for something a little different. And unlike other envelope filters, the low parts count make this a super easy build.