Demo: https://www.youtube.com/watch?v=z-tGAeBtxNY
The Brizachord is an open-source instrument and chord machine inspired by the Suzuki Omnichord. It features:
- 240 possible chords from 12 root select switches, 4 quality select switches, and 5 extension select switches
- Drum machine triggered by internal sequencer with toggleable chord pattern synchronization ("Groove"), adjustable BPM
- Velocity sensitive, multitouch capacitive strum plate for autoharp-style use
- Self-contained design with its own digital oscillators, amplification, and speaker (i.e, not a MIDI-only type deal).
It was designed by me and will be used in workshops held with the Audio Engineering Society at the University of Florida in Fall 2025.
The instrument is based on the Daisy Seed audio development board and the associated libdaisy library for programming its STM32H7 MCU. It uses a Bela Trill Bar sensor for the strum plate and an Adafruit PAM8302A Class-D breakout for the amplifier.
The hardware is designed for removability and reuse of the Daisy Seed and the Trill Bar.
- Improve documentation of all functions
- USB MIDI (important)
- MIDI clock synchronization
- Data-driven CSV reading for sequencer patterns so that users can create their own more easily
- Adjust Trill Bar JST cutout position
- Change corner mounting holes to M3 sized
- Find 12mm switches that are compatible with large black/white circular & square bezels to use for root selects, pattern selects
- Remove unused speaker routing holes and move Trill Bar headers to bottom of board
- Onboard power is possible, but unlikely to be implemented by me on this iteration of the board
The firmware is based on a custom fork of libdaisy that updates the language version to C++17 and merges @giulomoro's Trill support PR (electro-smith/libDaisy#657). When this PR is merged upstream, the project will probably migrate to standard libdaisy.
All software/firmware is licensed under GPLv3. All hardware (schematic, design) is licensed under CERN-OHL-S.