The Music Thing Spring Reverb is a flexible, easy-to-build voltage controlled DIY mono spring reverb module. Traditional guitar reverbs are tuned to the sound of the guitar and the amplifier it is played through. This circuit is different; designed to be relatively clean and high-fi, with a lot of bass response. It can also be abused and driven into (externally patched) feedback, as the demo below shows.
The circuit, plans and PCB/panel designs are open source and shared under Creative Commons.
Works with a variety of spring reverb tanks, or with the Accutronics BTDR-2 reverb ‘brick’ designed by Brian Neunaber
Includes PCB panel designs that can be very cheaply produced.
Vactrol crossfade between dry and wet
Tilt EQ on the reverb send to tune the voice of the reverb
X-Fade input so the module can also be used as a standalone vactrol crossfader (crossfade demo)
Attenuverter on the crossfade CV input
Options for reverb tank connection and placement including front panel sockets.
Optional (unbuffered) PCB connections for 100% wet and post-EQ dry outputs
6hp wide (NB: If using the brick, mounted horizontally, the brick extends 5mm over the PCB to the left of the module, around 25mm back from the front panel, so mount the reverb next to a shallow module)
Around 60mm deep including a phono plug for the reverb tank coming from the back. Just 35mm deep if you mount the reverb connections on the front panel