Minichord Is A Pocket-Sized, Open-Source Omnichord-Style Synthesizer
Developer Benjamin Poilve let us know about minichord, an open-source (CC BY-NC 4.0) project for building a portable ‘mini-Omnichord’ synthesizer.
Featuring both basic chord selectors and further buttons that enable you to add flavour to them (major, minor, seventh, etc) it certainly takes some design cues from Suzuki’s classic Omnichord. You even get an Omnichord-style sensor bar that enables you to play individual notes from the chord or arpeggios.
Inside there’s a full subtractive synth engine, and space for 12 presets. Editing can be handled by connecting the minichord to a computer over USB and opening up the web-based interface. Presets can also be shared between users.
Here’s what Poilve has to say about it:
“This project is born from two things: my love for easy to use/not keyboard-based synthesizers and the incredible Audio library of PJRC (the teensy 4.0 manufacturer).
I realized it would be possible to build a very powerful, very small synthesizer. Of course, the exterior design is a respectful nod to the Omnichord, but the synthesis capability and customisability are much greater and derive from my interest in analog synthesizers.
The buttons on the right allow you to create both simple and complex chords. In particular, I wanted to give the possibility to create “slash chord” (where the root of a chord is replaced by a different note) as it is something that is commonly used in guitar chords progressions. The touch zone on the left allows you to strum notes, as well as pick them.
The thing I’m the most proud about this project is the preset and configuration scheme. Early on I realized that given the number of parameters of my synthesis scheme, it would be too complicated to manipulate parameters in the code, and the minichord had limited space for potentiometers. So I decided to create an interface to edit the internal parameters from a computer. To do that, I used MIDI Sysex signals, because those signals are compatible with webMIDI. That means that all the internal parameters of the device are user-configurable live simply by connecting the minichord to a computer and opening a webpage!”
minichord Video Demo:
Full documentation is available via Github and the project site.
