Bass keyboard

The Synharmonium

is a new kind of musical instrument.

Designed to be easy to use, and more importantly, easy to make good music with. It uses the accordion's Stradella bass system to make it easy to play notes and chords that go well together, the Omnichord's strum plate to give texture to that harmony, and a piano keyboard for a familiar way to add a melody.

A Well-Tempered synthesizer.

One of the goals of the Synharmonium is to create an instrument which uses an algorithmic implementation of just intonation. In other words, it tunes every note in a perfect mathematical relation to the root of whatever chord is being played. Where other instruments simply have every note an equal distance apart and call it done ("Equal Temperament"), the Synharmonium will ensure they are always in simple ratios to each other, allowing for a more resonant sound. But if you want to play with those other instruments, you always have the option to disable this feature and return to the more common tuning.

Digital where it's needed, analogue where it counts.

The Synharmonium uses a digital system to implement that tuning algorithm. But once the computer has decided what frequencies are best, everything that can analogue will be, including the envelope generators, drum machine oscillators, and effects. This allows it to have that classic analogue sound with none of the downsides.

But, if you want to use the Synharmonium's tuning technology with an external synthesizer, it also has full MIDI compatibility (with both DIN and USB).

Free to build, modify, and hack

The hardware and software are all open source. I intend to base the control and tuning systems on an Arduino, which is beginner-friendly and hackable by design. I haven't the means to build these machines on a large scale at the moment (though I've thought about selling an "official version" as a preassembled machine and a kit, lmk what y'all think), so for the time being I will just be providing the design for free. That means you get to build it (!) until I know what I'm doing.

A work in progress.

I'll be real with y'all: I don't know what I'm doing. Every part of this project is a skill that I am learning as I go. But I think this is a thing that deserves to exist, so I intend to let it. It will probably take some time, as I am currently pursuing degrees in Electrical Engineering and Computer Engineering, so I can only work on the Synharmonium in my free time.

If you have skills that could help this process along, feel free to join the project. Do send me an email first though, I'd like to know who I'm working with!

Here goes nothin'!

-Evan