This idea has been floating around in my head since the first pcomp assignment - to make a creative switch. Around the same time, for my generative music class, we were asked to listen to Terry Riley's In C. And in my fabrication class, we were asked to make multiples of something. It's nice tracing back to the little pieces that fit together and took their time to marinate ... hopefully translating to a completed project in 6 weeks.

The idea is inspired by a music box - which can be looked at as multiple discs with binary encoded rhythms. Each note on the music box has a disc associated with it (though all the discs are fused in the above picture), and each disc has ridges that mark an 'on' state. The binary state of the discs was the connection to the pcomp assignment, and the repetition of form of discs related to the fabrication assignment. The connection to In C is perhaps less direct – the composition consists of 53 short musical phrases (which can be played on any instrument), with suggested rules for how to go about playing them, leading to an almost infinite number of possibilities. The start of each phrase need not sync up with the rest – ie it can be transposed, maintaining time. Since each phrase in repeated indefinitely, there's a circularity to it, and transposing a phrase would lead to a different relationship with the phrases being played, while maintaining this circularity, or looping.

I'd like to make a modular version of the music box – allowing people to add and remove discs with binary-encoded rhythms as they please. Similar to the music box, each position they can place the disc in corresponds to a specific sound. This will probably be a digital sounds, though the idea of using physical sounds and exploring materials is also very tempting. I created a digital prototype to see if this interaction was fun enough to keep exploring

http://experiments.playdo.io/music-discs

Each of the rectangle areas would have a spinning shaft, with a square peg on it. The discs at the bottom of the images are some examples of the shapes possible – though there's 2^32 possibilities. The discs 'make contact' with the red bar on the side and trigger a sound as long as they're touching the bar. Each of the rectangle areas (players?) has a specific note associated with it. The square peg allows for 90degree transpositions, though it could also be a triangle or hexagon or octagon. This idea came as a solution to the problem of losing time if it was a circular peg – it would be extremely hard to place a disc in exactly the right spot to maintain time. I guess sometimes problems are good fuel for interesting features.

Translating this to physical world is a little daunting. After getting some advice from Danny and Ben, I have a reasonable idea of next steps, but there's plenty to figure out and test, and things I will only uncover by building and observing.

The idea is to use a single stepper motor, and perhaps start by limiting myself to 4 spinning-shafts/players (I need a better word for this). I'll need timing pulleys and belts, maybe a d-shaft, and bearing or bushings. For sensing the on/off state of the discs, I'm contemplating using a light sensor as a switch - it'll get covered whenever the spokes of the discs are long. I'd want a clear indication that this is what's happening, and physically making contact with a material would have been great for this – but this needs some more thought and experimentation.

I'm going to start off with a single unit and the motor, here's a list of things to test/figure out

  • find and order all the parts for the mechanics of a single unit
  • test the feasibility of a light sensor for detecting state
  • test the interaction of placing or removing a disc which the shaft is spinning
  • figure out a way to get a square peg sitting on the shaft well, and ensure the disc sits on this well
  • figure out how to control the stepper better – first efforts had some weird results
a drawing/plan for a single unit

[ there's a couple of other ideas brewing, which I may turn to if this seems like too much for this time frame... lets see ]