Synth DIY Facebook group member Craig Barnes has created a bi-timbral synth controller. With 64 split upper/lower channels of Control Voltage (CV), this Teensy 4.1-based wonder also features 56 channels of shift registers for digital control.

The controller features four LFOs for FM, TM, AM, and PWM (upper and lower). Two noise circuits and Voltage Controlled Amplifiers (VCAs) provide further sonic possibilities. This is a seriously impressive thing to do on protoboard, as attested by the sheer volume of wiring around back.