This video, via Tom Whitwell, demos his Music Thing Modular Spring Reverb, a spring reverb module for Eurorack modular synths. 

Controls:

• Top knob is reverb level.
• Right hand smaller knob is Tilt, a simple hifi-style tone control that changes the colour of the reverb.
• Left hand smaller knob is Control, an attenuverter control for the incoming CV. 12 o’clock = no CV, clockwise = increasing CV, anticlockwise = inverted CV.

Patch details:

DPO sine waves sequenced by Turing Machine and Wogglebug. Gated through QMMG, envelopes from Maths. The CV input makes 80s-style gated reverb and pseudo-reverse reverb possible.

Information, schematics, PCB files are available at the Music Thing site. The design and all documentation are Creative Commons Licensed.