Available as an assembled Module and as a DIY project.
This Module is currently available.
Specs are approved by the manufacturerAnalog Spring Reverb
The SPRING REVERB utilizes an analog spring tank to process audio signals. This type of signal conditioning is useful in synthesizing complex spatial qualities, for timbre refinements and for the simulation of acoustical ambience. Two outputs are provided: one is a pure reverberated image of the inout signal: the other is a manually variable mix of the original signal and its reverberation.
https://prismcircuits.net/products/serge-modular-spring-reverb
These merchants probably sell this module. Huh?
Mosky Audio Spring Reverb
Mosky Audio Spring Reverb 2010s Pink
Mosky Audio Spring Reverb
Mosky Audio Spring Reverb
Mosky Audio Spring Reverb
Befaco Spring Reverb