DIY guru Mitch Altman has been busy expanding ArduTouch, the $30 kit board he designed to teach synthesis and coding. And now you can turn it into a bunch of other synths – with some new videos to who you how that works.

You’ll need to do a little bit of tinkering to get this working – though for many, of course, that’ll be part of the fun. So you solder together the kit, which includes a capacitive touch keyboard (as found on instruments like the Stylophone) and speaker. That means once the soldering is done, you can make sounds. To upload different synth code, you need a programmer cable and some additional steps.

Where this gets interesting is that the ArduTouch is really an embedded computer – and what’s wonderful about computers is, they transform based on whatever code they’re running.

ArduTouch is descended from the Arduino project, which in turn was the embedded hardware coding answer to desktop creative coding environment Processing. And from Processing, there’s the idea of a “sketch” – a bit of code that represents a single idea. “Sketching” was vital as a concept to these projects as it implies doing something simpler and more elegant.

For synthesis, ArduTouch is collecting a set of its own sketches – simple, fun digital signal processing creations that can be uploaded to the board. You get a whole collection of these, including sketches that are meant to serve mainly as examples, so that over time you can learn DSP coding. (The sketches are mostly the creation of Mitch’s friend, Bill Alessi.) Because the ArduTouch itself is cloned from the Arduino UNO, it’s also fully compatible both with UNO boards and the Arduino coding environment.

Mitch has been uploading videos and descriptions (and adding new synths over time), so let’s check them out:

Thick is a Minimoog-like, playable monosynth.

Arpology is an “Eno-influenced” arpeggiator/synth combo with patterns, speed, major/minor key, pitch, and attack/decay controls, plus a J.S. Bach-style generative auto-play mode.

Beatitude is a drum machine with multiple parts and rhythm track creation, plus a live playable bass synth.

Mantra is a weird, exotic-sounding sequenced drone synth with pre-mapped scales. The description claims “it is almost impossible to play something that doesn’t sound good.” (I initially read that backwards!)

Xoid is raucous synth with frequency modulation, ratio, and XOR controls. Actually, this very example demonstrates just why ArduTouch is different – like, you’d probably not want to ship Xoid as a product or project on its own. But as a sketch – and something strange to play with – it’s totally great.

DuoPoly is also glitchy and weird, but represents more of a complete synth workstation – and it’s a grab-bag demo of all the platform can do. So you get Tremelo, Vibrato, Pitch Bend, Distortion Effects, Low Pass Filter, High Pass Filter, Preset songs/patches, LFOs, and other goodies, all crammed onto this little board.

There, they’ve made some different oddball preset songs, too:

Platinum hit, this one:

This one, it sounds like we hit a really tough cave level in Metroid:

Open source hardware, kits available for sale: