Inspired by the popular flash-based ToneMatrix melody-sequencer, Andrew decided he wanted a tangible 16×16 LED matrix instrument. Sure, there are premade options but none quite fit the bill –
the Bliptronic 5000 just doesn’t have enough lights. All the existing 16Ã—16 equivalents were more money than I wanted to pay: A Tenori-on costs something like $1000. Four Bliptronic 5000s cost $200. A monome two fifty six costs $1400. I was thinking more along the lines of $50. Besides which, I thought to myself, it would be fun to make it myself.
I had trouble thinking of a way to set up 256 switches over the LEDs without obscuring them or spending too much, until I remembered an effect I had noticed messing about with transistors years ago – you can make a touch switch out of a couple of transistors arranged in a Darlington configuration. I could arrange them in a matrix like the LEDs so that the only per-switch cost was a couple of small sections of wire. This could be threaded through an acrylic sheet which would serve a dual purpose – to diffuse the LEDs and to hold the switch wires. I originally thought I would have 4 solder connections to the PCB per switch, but then I realized that that would be too difficult to solder and that it would be better to just connect my switch matrix at the edges.
His firmware (running on an ATmega328) sports a hefty feature list with random, game of life, & microtonal modes – plus multiple waveforms, a tuning editor, preset saves and more. The finished product is pretty dang impressive – and definitely unique compared to other musical grids out there. I’m especially digging that loose aesthetic resulting from the diffusion panel/touch switch bezel – nice design!
Continue reading the build story on Reenigne blog. [via Hack a Day]