Home : Tune Toys : Expresso 
  Expresso takes a simple musical expression (literally "X") and mutates it. In each generation, transformations are applied to components of the expression. This is a fractal technique known as an L-system. The more generations there are, the larger and more complex the expression gets (and the longer it can take to compute). The output varies wildly, from boring to fascinating. Press "Mutate" a few times till you get something that looks interesting, then click on the image to play it. See Composer's Quarry for examples of output.

Transformations:
Seed:
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Generations:
Phrase for X:
# of Tracks:
Randomize patches:
 

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After 20 generations the expression "X" became this:
transpose(((((shuffle(((transpose(((arpeggio(((X+transpose(X,12) ) +transpose(((arpeggio(X) +transpose((X+transpose(X,7) ) ,4) ) +transpose(step(X,12) ,7) ) ,12) ) ) +transpose(transpose(((X+transpose(X,12) ) +transpose(X,12) ) ,-7) ,4) ) +transpose(transpose((shuffle(X) +transpose(X,7) ) ,-5) ,7) ) ,4) +transpose(transpose(((X+transpose(X,12) ) +transpose(step(X,12) ,7) ) ,-5) ,12) ) |transpose(echo(transpose(X,-7) ,4,6) ,-5) ) ) +transpose((((transpose((step((transpose(transpose((X+transpose(X,12) ) ,-7) ,4) +(((X+transpose(X,4) ) +transpose(X,7) ) +transpose((X+transpose(transpose(X,-5) ,7) ) ,12) ) ) ,12) +transpose((echo((shuffle(X) +transpose(echo(transpose(echo(X,4,6) ,-7) ,4,6) ,12) ) ,4,6) +transpose((transpose(X,4) |shuffle(X) ) ,12) ) ,7) ) ,-7) |((((((step(X,12) +transpose((step(X,12) +transpose(((((X+transpose(X,4) ) +transpose(X,7) ) |transpose(X,-5) ) +transpose(step((X+X) ,12) ,7) ) ,12) ) ,7) ) +transpose(((transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-7) +transpose(transpose(X,-5) ,12) ) +transpose((transpose((arpeggio(((X+transpose(X,4) ) +transpose(X,7) ) ) +step(transpose(X,-5) ,12) ) ,-7) +(transpose(X,4) +transpose(transpose(X,-7) ,7) ) ) ,12) ) ,12) ) +transpose(((((transpose(step(((transpose(transpose(X,-5) ,-7) +transpose(transpose((X+transpose(X,7) ) ,4) ,4) ) +transpose(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-5) ,7) ) ,12) ,-5) +transpose(transpose(shuffle((transpose(transpose(X,-5) ,-5) +transpose(step((arpeggio(X) +((X+transpose(X,4) ) +transpose(X,7) ) ) ,12) ,12) ) ) ,-5) ,4) ) +transpose(transpose(((transpose(transpose(X,4) ,4) +((X+transpose(X,4) ) +transpose(X,7) ) ) +transpose(step(((((X+transpose(X,12) ) +(X+X) ) +transpose(transpose(X,-5) ,4) ) +transpose(transpose(X,-7) ,7) ) ,12) ,12) ) ,-7) ,7) ) +transpose((transpose(transpose(X,-7) ,-5) +transpose(transpose(arpeggio(X) ,-5) ,7) ) ,4) ) +transpose((((transpose((X+transpose(echo(X,4,6) ,12) ) ,-7) +transpose(((transpose(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) ,-5) +transpose((((X+transpose(X,12) ) +transpose(X,-5) ) +(echo(X,4,6) +transpose(transpose(X,-5) ,7) ) ) ,4) ) +transpose(step(((X+transpose(step(X,12) ,4) ) +transpose(X,7) ) ,12) ,7) ) ,7) ) +transpose(transpose((((shuffle((X+transpose(X,12) ) ) |X) +transpose((arpeggio(X) |arpeggio(X) ) ,4) ) +transpose((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(arpeggio(X) ,7) ) ,7) ) ,4) ,4) ) +transpose(transpose((echo(X,4,6) +transpose(shuffle(transpose(X,-5) ) ,12) ) ,-5) ,7) ) ,7) ) ,4) ) +transpose(arpeggio(echo(echo(transpose(transpose(X,-7) ,-5) ,4,6) ,4,6) ) ,7) ) +transpose(shuffle(transpose(echo(X,4,6) ,-7) ) ,4) ) +transpose((transpose(transpose(transpose((transpose(transpose(echo(X,4,6) ,-5) ,4) +transpose(transpose((X+transpose(X,7) ) ,-7) ,7) ) ,-7) ,-5) ,4) +transpose(echo((((X+(step(X,12) +transpose(transpose(X,-5) ,12) ) ) +transpose(step((X+transpose(X,7) ) ,12) ,12) ) +transpose(transpose((shuffle((X+transpose(X,7) ) ) |((X+transpose(X,4) ) +transpose(X,7) ) ) ,-7) ,7) ) ,4,6) ,12) ) ,7) ) ) +transpose(((transpose((step(transpose(X,-7) ,12) +transpose(echo(arpeggio(X) ,4,6) ,12) ) ,-5) +transpose(step(transpose((transpose((((X|X) +transpose(transpose(X,-5) ,7) ) +transpose(echo(transpose(X,-5) ,4,6) ,12) ) ,4) +transpose(transpose(echo(echo(transpose(X,-5) ,4,6) ,4,6) ,4) ,12) ) ,-7) ,12) ,4) ) +transpose((step(transpose((((((transpose(X,-7) +transpose(arpeggio(X) ,4) ) +transpose((X+transpose(X,12) ) ,7) ) +transpose((X+X) ,7) ) +transpose(transpose(arpeggio((X+transpose(X,12) ) ) ,4) ,4) ) +transpose((transpose(X,-5) +transpose((X|transpose((X|X) ,-7) ) ,12) ) ,7) ) ,-5) ,12) +transpose(((step((transpose(X,-5) +transpose((X+transpose(X,7) ) ,7) ) ,12) +transpose(((arpeggio(X) +transpose(((X|X) |transpose(X,-7) ) ,4) ) +transpose(shuffle(X) ,7) ) ,7) ) +transpose(transpose((transpose(transpose(transpose(X,-7) ,-7) ,-7) +transpose(transpose(step(X,12) ,-5) ,-7) ) ,-7) ,7) ) ,-5) ) ,7) ) ,4) ) +transpose(step(step(transpose(((transpose(transpose(transpose((X+transpose(X,12) ) ,-7) ,-5) ,-5) +transpose((transpose((X+transpose(X,12) ) ,4) +transpose((transpose(transpose(X,-5) ,-7) +transpose((X+transpose((transpose(X,-7) +X) ,7) ) ,7) ) ,7) ) ,4) ) +transpose(transpose(((transpose(X,-7) +transpose(((X+transpose(transpose(X,-7) ,4) ) +transpose((X+transpose(X,7) ) ,7) ) ,4) ) +transpose((shuffle(X) |(X+transpose(X,7) ) ) ,7) ) ,-5) ,7) ) ,4) ,12) ,12) ,7) ) ,12) ) +(transpose(step(transpose(transpose((((X+transpose(transpose(X,-5) ,7) ) +transpose(transpose((echo(X,4,6) +transpose(transpose(X,-7) ,7) ) ,-5) ,12) ) +transpose(step(transpose(step((X+transpose((X+transpose(X,12) ) ,7) ) ,12) ,-7) ,12) ,12) ) ,4) ,-7) ,12) ,-7) +transpose(transpose(((transpose(transpose(echo(((((X+transpose((X+transpose(X,12) ) ,4) ) +transpose(echo(X,4,6) ,7) ) +transpose(echo(((X+transpose(X,4) ) +transpose(X,7) ) ,4,6) ,4) ) +transpose(((X+transpose(X,7) ) +(X|X) ) ,7) ) ,4,6) ,4) ,-7) +transpose((transpose((((arpeggio(X) +transpose(transpose(transpose(X,-5) ,-7) ,7) ) +transpose(step(echo((X+transpose(X,7) ) ,4,6) ,12) ,4) ) +transpose((echo(transpose(transpose(X,4) ,-5) ,4,6) +transpose((((X+transpose(X,-5) ) +transpose(arpeggio(step(X,12) ) ,4) ) +transpose(transpose(transpose(X,-7) ,-7) ,7) ) ,12) ) ,7) ) ,-5) +transpose(echo(echo(transpose((step((((X+transpose(X,4) ) +transpose(X,7) ) +transpose((((X+transpose(X,7) ) +transpose((X+transpose(X,7) ) ,4) ) +transpose(X,7) ) ,7) ) ,12) +transpose((X+transpose(arpeggio(X) ,7) ) ,12) ) ,-5) ,4,6) ,4,6) ,12) ) ,7) ) |transpose(arpeggio(echo(shuffle(shuffle(step(X,12) ) ) ,4,6) ) ,4) ) ,-7) ,7) ) ) +transpose((transpose(((shuffle((transpose(transpose(transpose(transpose((((X|X) +transpose(shuffle(X) ,4) ) +transpose(transpose(X,4) ,7) ) ,-5) ,4) ,4) ,4) |echo(((echo(transpose(shuffle((X+transpose(arpeggio(X) ,12) ) ) ,4) ,4,6) +transpose(((step(arpeggio(X) ,12) +transpose(((transpose(transpose(X,4) ,-7) +transpose(arpeggio(X) ,4) ) +transpose(transpose(X,-5) ,7) ) ,4) ) +transpose((echo(X,4,6) +transpose(arpeggio(echo(X,4,6) ) ,7) ) ,7) ) ,4) ) +transpose(transpose(X,-7) ,7) ) ,4,6) ) ) +transpose(echo((transpose(step((transpose(X,-5) |shuffle(X) ) ,12) ,4) +transpose(arpeggio((step(shuffle(X) ,12) +transpose(step(transpose(X,-5) ,12) ,7) ) ) ,7) ) ,4,6) ,7) ) +transpose(((shuffle((echo((step(X,12) +transpose(step(transpose(X,-5) ,12) ,7) ) ,4,6) +step(transpose(transpose((transpose(X,-5) +transpose(X,7) ) ,-5) ,-5) ,12) ) ) +transpose(transpose(step(((step(X,12) +transpose((transpose(X,4) +transpose(transpose(X,-5) ,7) ) ,7) ) |(transpose(shuffle(X) ,4) +transpose(X,7) ) ) ,12) ,4) ,4) ) +transpose(transpose(((transpose(echo(arpeggio((X|X) ) ,4,6) ,4) +transpose((transpose(echo(transpose(transpose(X,-7) ,-5) ,4,6) ,-7) +transpose(transpose(transpose(((X+transpose(transpose(X,-7) ,4) ) +transpose(X,7) ) ,-7) ,-5) ,12) ) ,12) ) +transpose(arpeggio(transpose(arpeggio(transpose(X,-5) ) ,-5) ) ,7) ) ,-7) ,7) ) ,12) ) ,-5) +transpose((transpose(transpose(shuffle(transpose(echo(((shuffle(transpose(((transpose(X,4) +transpose(X,4) ) +transpose(shuffle(X) ,7) ) ,4) ) |(echo(transpose(X,-7) ,4,6) +transpose(echo((echo(X,4,6) +transpose((X+(X+transpose(X,7) ) ) ,7) ) ,4,6) ,7) ) ) +transpose(transpose(transpose((((X+transpose(X,4) ) +transpose(X,7) ) |transpose(X,-5) ) ,-5) ,4) ,7) ) ,4,6) ,-5) ) ,-7) ,-5) |transpose(transpose(shuffle((step((((transpose(transpose(X,-7) ,-7) +transpose((X|X) ,12) ) +transpose(X,-7) ) +transpose(transpose((transpose(step(X,12) ,-7) +transpose((((X+transpose(X,12) ) +(X+transpose(X,12) ) ) |(X+X) ) ,12) ) ,-7) ,12) ) ,12) +(X+transpose(X,7) ) ) ) ,-5) ,-5) ) ,7) ) ,12) ) +transpose(transpose(echo(transpose(echo(shuffle((transpose((transpose((transpose(X,4) |X) ,-7) +transpose((transpose(X,-5) |((shuffle(X) +transpose(step(X,12) ,4) ) +transpose(transpose((X|X) ,-7) ,7) ) ) ,7) ) ,-5) +transpose(shuffle((X+transpose((X+transpose(X,7) ) ,7) ) ) ,7) ) ) ,4,6) ,-5) ,4,6) ,-5) ,7) ) ,-7)
random seed used was 86791632

The algorithm for Expresso is written in KeyKit, and here's the source code.