This is an ‘encore presentation’ of a post I originally wrote for my old blog — it was lost in the great blog fire of ’12 and (thank you Wayback Machine) is being edited and reposted here since it seemed to be pretty popular at the time. If you’re going to follow along with what I’ve done, give a quick look at Step 4 where I discover I’ve been using the wrong chip and have to change things up a bit.

The source code is hosted on Github here. There’s not really too much of it, but it’s worth making public for people.


I’ve long had an interest in experimental electronic music, so I’m excited that I have something to share in that arena.

In the past I’ve mentioned my wonderful wife (who is wonderful, if I didn’t say so), and for Christmas she doubly earned that distinction by buying me a Gakken SX-150 Analog Synthesizer. As far as a ‘kit’ goes, it isn’t much to speak of — just installing the pre-built board and speaker into the plastic case and wiring up the stylus controller — but it is such a simple design that it seems built to be hacked on, and that’s what I wanted to do.

I did find a number of cool SX-150 hacks, but often they were a bit more advanced than I’m ready for, so I figured I’d start with something simple and slowly build on it and make this a multi-part project. Since I’m really enjoying getting into Arduino programming, an Arduino-based sequencer seemed like a good candidate — so let’s get started!

Continue reading