Cellular Auto-Granulator

This project was created as a response to a class assignment on dynamical systems and evolutionary programming in which we were asked to create systems that demonstrated emergent behaviour. I chose to explore granular synthesis because I felt there was a strong similarity between this sound synthesis technique and the idea of complex behaviour emerging from the interaction of smaller simpler parts. I also desired to break away from visual work which was the predominant form in this class.

Cellular Auto-Granulator is a piece of software that uses the action of cellular automata to perform real time granular re-synthesis of sampled sounds. It was built from scratch using java and max/msp.

The mapping from the [binary] cellular automaton to the granular synthesis engine is quite simple. At each step the number of cells with a value of 1 is counted and directly mapped onto a position in the sound sample being granulated. This value also controls how long the selected grain is to be looped. A number of these cellular granulators are wrapped in a msp polyphony object to produce a denser, more layered sound. The mapping was chosen because of the need to demonstrate emergent behaviour. I had hoped that I would be able to find a rule that when mapped in this fashion would allows cellular auto-granulator to reconstruct a recognizable sonic phrase from the orignal sample. I consider this to be emergent because as the length of each grain is between 20-100 milliseconds, the software cannot simply pick a section of the original sample that would be recognizable. The overall growth of the cellular automaton must be such that it can successively pick sufficiently spaced grains to reconstruct the original sounds.
The rule I eventually picked was Fredkin 2 (available from Mirek's Cellebrations), , which was able to yield the following results.

Reconstructed sonic phrases: thatyou.mov hugedoublebass.mov

An equally important goal, that was in fact achieved before the above one, of this project was to create an instrument that made an interesting sound that I could use in a live setting or as source material for composition. A little bit of randomness was added to the mapping to allow for more a diverse, less periodic soundscape to form. I was quite pleased with the results as it was my first foray into the world of microsound. Here are some raw recordings as well as a piece I made using the cellular auto granulator.

Composition: etude 3:diptych
Sample raw recording: raw1.mov raw2.mov