Combining his passion for music and making, The Mixed Signal offers a YouTube channel merging these topics. “Dedicated to the high-minded ideals of utter nonsense, reinventing the wheel, and occasional bits of education and entertainment,” he released DIY videos building an “Alien Drum Machine” and a “Stepper Motor Theremin.”

In his most popular video, he is 3D printing a tonewheel and getting lovely sounds out of it.

Tonewheels are essential parts of electromagnetic instruments like classic Hammond organs. An AC motor spins a dented disc, rotating fast near an electromagnetic pickup (think of an electric guitar). Because the dents contain magnetic parts, the pickup receives a steady electromagnetic pulse that can be turned into sound.

For a proof-of-concept, The Mixed Signal designed his own tonewheel.

Most of the parts were 3D printed, like the wheel itself, the pickup holder, and parts of the setup. He even wound the pickup using a stepper motor, a thin copper wire, and an Arduino. For the magnetic parts of the tonewheel, he used Protopasta’s Iron-filled PLA.

If you want to take a deeper dive, please watch the video below.

Our synth expert at All3DP found the “organ” actually sounds pleasantly warm and comes with a lovely distortion that could put a Hammond to shame.

https://www.youtube.com/watch?v=IZxV41eESZ4

(Source: The Mixed Signal. Lead image: Arduino.cc)