Spring Reverb mk1
The Spring module started out in 2011 as a perfboard design shared on the ModWiggler forum.
In 2013 it was launched as project and sold through Thonk, which was replaced in 2017 by an updated version that is wholly improved, with improved audio and a feedback circuit.
These are the files for the 2013 version:
Spring Reverb build and user manual – includes how to choose a spring reverb, how to calibrate the circuit, patch ideas and tips for getting the best results.
Document bundle includes manual, schematic, parts list, and design specifications for the panels
Spring Reverb_PCB Files Eagle and Gerber files for reverb PCBs and panels.