[queued] Hybrid Piano


New member
A few years back I started building a hybrid piano with Teensy 4.1 and other components – analog and digital.

Hybrid = acoustic piano action + digital midi controller + other software features. Yamaha and Kawai sell hybrid pianos, but I wanted to build my own.

Recently all 88 piano keys are working, using a Kawai grand piano action.

I got in the habit of making a YouTube video documenting each development step (and mistakes). But since I now play the piano more than work on it, the pace of videos may slow down.

Fragments of project are on GitHub. On my to-do list is improving GitHub content - code, pcb, etc.

Project links:




The project is as much about experimenting as getting anything done. So, I’ve built two different functioning architectures and am working on a third approach. Here is a picture showing both types of boards connected to the piano action:


In the center is my lower performance board (rectangular). If fully populated, it uses two Teensy 4.1 and connects to all 88 keys.

Surrounding it are six of my higher performance boards (square). Each board connects to 8 keys and uses two Teensy 4.1. If I built a complete piano with these boards, it would require 88/8*2 = 22 Teensy 4.1, plus 2 for pedal unit for a total of 24 Teensy 4.1.

Side view of higher performance board, both Teensy 4.1 are visible in this picture:


Whenever I had a Teensy question, this forum and PJRC documentation pages answered them.

simplified the design (third architecture),
last November finished getting all on GitHub,
continuing to improve,
and play the piano regularly.

One Teensy for processing piano hammer data.
Optionally a second for processing piano damper data.