Musical Gene Pool
An Experiment in Evolving Structure in Continuously-Playing Sound
Music " a fluid reality. The only thing that primitive polyphony, classical counterpoint, tonal harmony, twelve-tone serial music, and electronic music have in common is the principle of giving form to noise in accordance with changing syntactic structure".
- Jaques Attali, Noise
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Is it possible for a random soup of sounds to self-assemble into music? And can this be done by just giving a binary "like" when something sounds cool? Hypothesis: if there are enough "likes" from enough people over enough time, and if the data representation is sufficiently plastic, the answer is...Yes, But.

But those are two big if's. Expecially the one about the data representaion being plastic. Here's what I mean: the soup of sounds should have no (or very few) assumptions about music. But it can be altered by continual interaction - and the more versatile, the better. The idea is that all expressive sound should emerge as a function of people clicking when they like what they hear. This means that musical knowledge has to somehow be transfered (slowly) from human brains to the data representation.

The Musical Gene Pool is an attempt at making this transfer by way of a genetic algorithm - a simulation of Darwinian Evolution, where random mutation is filtered by selection pressures, causing some structures to survive and others to die off.

Published Chapter
An earlier version of the Musical Gene Pool is described in: Evolving Structure in Liquid Music, which is chapter in the book The Art of Artificial Evolution,
(editors: Penousal Machado and Juan Romero)
Intended Use
The intended use of this is as a web-based site where many people can visit, click a few times, and move on...until it starts to sound interesting, and then people would stay longer and nudge it in new directions. If you dare to hit the 'Start Random' button, be warned: it takes a long time, and if you prefer "Mary Had a Little Lamb" over Morton Subotnick and Bela Bartok, you may be dissapointed. Not to say that this comes anywhere near Bartok's ability to make music...simply to say that Bartok requires listening with 'open ears' - it taps a larger sonic vocabulary than Mr. Rogers.

Also, this is not 'music composition' in any conventional sense. Think of it as a self-evolving sonic ecology, intended to be nudged occasionally by humans. Take a John Cage attitude, and welcome serendipity. Select one of the examples above to hear gene pools that have undergone some interactive evolution.

The swirling sonic organisms help to explain the way it works, but it tends to distract from pure musical judgement. Select 'Toggle View' to switch visuals on or off.

(c) 2012 Jeffrey Ventrella

How Does it Work?
Many evolutionary music systems require the user to select for musical aspects in a piecemeal fashion, whereas the Musical Gene Pool is experienced as continuous sound throughout the entire process, as follows: a human listener gives fitness rewards after sounds (organisms) emerge from the gene pool, take turns playing, and then return back to the pool. Organisms start out unicellular (one sound), but as the listener selectively rewards random sequences deemed more musical than others, some organisms join up to form larger, multicellular organisms - which become phrases or extended musical gestures. Genetic operators of splitting, death, replication, and mutation occur in the gene pool among rewarded organisms. This results in gradual evolution of structure as the sound continues to play. This emerges in response to the listener's own internal emerging musical language, based on accumulated musical memory.

This structure is liquid - continually able to flow and re-arrange to allow serendipity. While there is a limit to organism length (duration of phrases), it is proposed that the interactive scheme could be adjusted to evolve increasingly larger organisms, and hence, longer musical passages. These would essentially be mobile chunks of linear music with self-similarity in their structures - revealing the histories of their evolution.