For many years I’ve had the idea of making a MIDI controller in the shape of an English concertina. Now that I have my Glowforge and am comfortable with using it, I thought it might be possible for me to build one. But let’s take a step back. What’s a MIDI controller? What’s a concertina? And why would anyone want such a thing?
MIDI stands for Musical Instrument Digital Interface. It’s the standard way to connect the part of an electronic instrument the player pokes and prods (a keyboard, say) to the part of the instrument that turns the pokes and prods into sound (usually a synthesizer). The part the player pokes and prods is called the “MIDI controller.”
A concertina is a kind of squeeze box that’s roughly circular in cross section, with buttons on each end and a bellows in the middle. When you operate the bellows and push the buttons, air goes through little devices called “free reeds” and noises come out. If you do it well enough, you get music. The “English” version of the concertina is a fully chromatic instrument with a particular arrangement of buttons and reeds that makes playing in various different keys
So that’s what I wanted: A MIDI controller in the shape of an English concertina. I wanted one because I can (sort of) play the concertina, and I’d like to operate a synthesizer. There are almost none in the world, so the only practical way to get one is to design and built it. So I did. Here’s what it looks like:
As you can imagine it’s got lots of parts inside. Here a picture of some of them:
This shows the electronics inside the left side. The wooden dodecagon is the left keyboard assembly containing 28 switches and lots of wires in four layers of Baltic birch plywood. The right keyboard assembly is similar, but the electronics is much simpler.
Here’s one of the keyboard faces:
The keys are made of Delrin and so slip nicely through holes, reach into the keyboard assembly and operate the switches. Almost all of the parts, including the bellows, were made on the Glowforge.