Music and Synth DIY

Effects, Eurorack, Synth DIY

MI Rings

Built this from a PCB from – mutated panel is from

The Davies (?) style knobs – the white and grey ones under the two top controls – are from AliExpress. Although supposedly 6.35mm, they needed boring out slightly before they’d fit but otherwise nice and cheap compared to the usual alternatives.

This is an 0603 SMD PCB, but relatively straightforward – I’d put it on par with MI Clouds as a build (same WM8731 codec and a LQFP-64 package ARM microcontroller).

Where the Eagle files are available, like they are with the open source MI stuff, I find it’s best to start by generating an IBOM, which speeds up placing the components and saves having to hunt around the board for each one. “Highlight pin 1” is a nice sanity check as well for IC orientation and diodes etc.

Worked first time, so no troubleshooting notes.