DIY MIDI + Tone Sequencer (2020)

This handmade sequencer can make sound from its internal speaker, plug into a speaker with its 1/4” output jack, or send MIDI to a computer. It uses a Teensy LC microcontroller programmed in Ardiuno, a small 5W audio amplifier chip, 8 potentiometers, 4 LEDs, a micro usb port for power, and a 1/4” output jack.

The four white knobs each control one note. The four green and yellow knobs control how the sequencer will play these notes:

Top left: Step speed

Top right: Number of steps played

Bottom left: Root note of scale

Bottom right: Volume