Solenoids
Hardware Project, 2024
A small opto-isolator box built from a readymade board and Eurorack-compatible jacks. Connecting solenoids or any other components that draw a high electrical load is usually dangerous with Eurorack modular synths. While the ±12V sounds quite powerful, many bus boards only deliver around 1-5A. To not risk any damage to any of the modules in the system, I use a prefabricated opto-isolator MOSFET board made for usage with light fixtures.
See the project in sync with the rest of the synthesizer here.
The goal was to send up to 4 trigger/gate/control voltages from the modular synthesizer to solenoids. Which then hit acoustic instruments. Most interestingly, the magnet flicking back and forth was already a surprisingly nice percussive sound.
Using 3.5 mm jacks everywhere for connecting with the modular level signal, as well as connecting the actuators with the control board. It would be best to use different kinds of connectors for these purposes, but there is a ubiquitous amount of 3.5 mm patch cables available.
Luckuly the µMixa by noisio perfectly suits the little solenoid box. With five mono high-z inputs it is suited to take up to five piezo contact mics is input and send out a mixed down signal that wont harm the modular synth. Having an arrangement of sound bowls at hand I drew up the next patch:
For performance purposes It will be usefull to bring the messy wiring in 3U high Eurorack panel to fit in one of the tiny Eurorack compatible cases.
