Here's another one of my recent Axoloti projects, finally finished. It's a spring synth with two contact mics under the hood, for stereo ambient sound textures.
Features of the RedSpring:
- 2x contact mics
- Exchangeable springs on pegs for different sounds
- Hollow red metal box with a nice resonating body, picking up taps and buttons presses too
- 4x resonant low-pass filters with cutoff knobs, gate and self-oscillation buttons
- Delay & Reverb audio fx
- Looping/infinite Delay switch
- Random fx modulation switch
- Headphone and regular L&R audio outs
- 2x 9V power sockets with different polarity, so you can run the instrument with center positive or center negative plugs and then forward the inverse to another device (e.g. run the RedSpring on center positive and forward center negative to a guitar pedal, requiring only one power supply)
When holding a LPF gate button, all sounds from the pickups go through that filter, giving the sound a bit of a pitch. When also holding down the resonance knob, the filter starts to self-oscillate. One can of course hold down multiple LPF buttons at the same time. The dry audio is also mixed with the filtered sound. Enabling the infinite delay switch will loop the sounds indefinitely and you can still play new sounds on top or even kind of "overdub" them to the loop for evolving soundscapes. The mod switch enables random modulation of various fx parameters whenever you press any of the filter buttons. It's usually a rather subtle effect, but sometimes you get really rough distortion from the random mod too.
Here are a few short videos from my Instagram account:
A little bit of percussion:
Some drones:
And here's a YouTube jam, together with La Conduttrice and two Lumanoise synths:
... and another one just with the RedSpring:
... aaaand one more 
... and some pictures:
Insides with the two contact mics under the rows of potentiometers:
