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:
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Generations:
Phrase for X:
# of Tracks:
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After 18 generations the expression "X" became this:
echo(((((shuffle((((shuffle(arpeggio((transpose(X,-7) +(((X+transpose((echo(X,4,6) +transpose((X+X) ,7) ) ,4) ) +transpose(step(X,12) ,7) ) +transpose(((shuffle((X+X) ) +transpose(transpose(X,4) ,4) ) +transpose(transpose(transpose(X,-5) ,-7) ,7) ) ,7) ) ) ) ) |((shuffle(step((X+transpose(step(X,12) ,7) ) ,12) ) +transpose(echo(transpose(transpose((step(echo(transpose(X,4) ,4,6) ,12) +transpose(arpeggio(transpose(transpose(X,4) ,-7) ) ,7) ) ,4) ,-7) ,4,6) ,4) ) +transpose(step(transpose((((((step((X+transpose(X,7) ) ,12) +transpose(transpose(step(X,12) ,-5) ,4) ) +transpose(transpose((X|X) ,-5) ,7) ) |transpose(transpose(X,4) ,-7) ) |arpeggio((transpose(X,-7) +transpose(shuffle(arpeggio((X+transpose(X,7) ) ) ) ,12) ) ) ) |(arpeggio(step(X,12) ) |(((X+transpose(transpose(X,-5) ,12) ) +transpose(((arpeggio(X) +transpose(X,4) ) +transpose((X+X) ,7) ) ,4) ) +transpose(transpose(X,4) ,7) ) ) ) ,4) ,12) ,7) ) ) +transpose(((((((transpose(echo(echo(X,4,6) ,4,6) ,-5) +transpose(((shuffle(transpose((X+X) ,4) ) +echo(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-7) ,4,6) ) +(((((X+transpose(X,12) ) +transpose(X,7) ) +transpose(arpeggio(X) ,4) ) +transpose((echo(X,4,6) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) ,7) ) +transpose(arpeggio(((X+transpose(X,4) ) +transpose(X,7) ) ) ,7) ) ) ,4) ) +transpose((arpeggio((arpeggio(X) +X) ) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-7) ) ,7) ) +transpose(transpose((((transpose(transpose(shuffle(X) ,-7) ,-7) +transpose(((transpose(shuffle(X) ,4) +transpose(shuffle(X) ,4) ) +transpose((((X+transpose(X,4) ) +transpose(X,7) ) +(X|X) ) ,7) ) ,4) ) +transpose((step(transpose(X,4) ,12) +step(transpose(X,-5) ,12) ) ,7) ) +transpose(step((echo(X,4,6) +transpose(((transpose(X,-7) +transpose(X,4) ) +transpose(transpose(X,-5) ,7) ) ,12) ) ,12) ,12) ) ,4) ,4) ) +transpose(transpose(shuffle(arpeggio(((X|arpeggio(X) ) +transpose(transpose(X,-5) ,7) ) ) ) ,4) ,7) ) |arpeggio(echo(((transpose((((X+transpose(X,12) ) +transpose(X,7) ) |(((X+transpose(X,4) ) +transpose(transpose(X,-7) ,7) ) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-5) ) ) ,-7) +transpose(arpeggio(arpeggio(X) ) ,4) ) +transpose(transpose((shuffle(X) |echo(X,4,6) ) ,4) ,7) ) ,4,6) ) ) +transpose(echo(transpose((echo(shuffle(echo((shuffle(shuffle(X) ) +transpose(transpose(X,4) ,-7) ) ,4,6) ) ,4,6) +transpose((step((echo(X,4,6) +(X|X) ) ,12) +transpose(arpeggio(step(((X+transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) ) +transpose((X|X) ,7) ) ,12) ) ,7) ) ,7) ) ,-5) ,4,6) ,7) ) ,4) ) +transpose((((echo(arpeggio(transpose((X+transpose(((step(X,12) +transpose(X,4) ) +transpose(transpose(X,-7) ,7) ) ,7) ) ,-5) ) ,4,6) |step(transpose(arpeggio(step(transpose(X,4) ,12) ) ,-7) ,12) ) +transpose(step(echo(arpeggio((shuffle(transpose(((X+transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) ) +transpose(shuffle(X) ,7) ) ,-7) ) +echo((step((X+transpose(X,12) ) ,12) +transpose(shuffle(X) ,12) ) ,4,6) ) ) ,4,6) ,12) ,4) ) +transpose(echo((((arpeggio(X) |arpeggio(X) ) |arpeggio(shuffle(arpeggio(X) ) ) ) |arpeggio(((((((X+transpose(transpose(X,4) ,4) ) +transpose(X,7) ) +transpose(shuffle(echo(X,4,6) ) ,4) ) +transpose(transpose(X,-5) ,7) ) |transpose((X+X) ,-7) ) |(((X+X) +transpose(((X+transpose(X,7) ) |echo(X,4,6) ) ,4) ) +transpose((X+(X+transpose(X,7) ) ) ,7) ) ) ) ) ,4,6) ,7) ) ,7) ) ) +transpose(shuffle(transpose(arpeggio(transpose(transpose(transpose(transpose((arpeggio(((X+transpose(step(X,12) ,4) ) +transpose(step(X,12) ,7) ) ) +transpose((X+X) ,-5) ) ,4) ,-7) ,4) ,4) ) ,-7) ) ,4) ) +transpose(transpose(echo(transpose(arpeggio(transpose(((((((X+arpeggio(X) ) +transpose(step(shuffle(X) ,12) ,4) ) +transpose(((X+echo(X,4,6) ) +shuffle(X) ) ,7) ) +transpose(step(step(shuffle(transpose(X,-5) ) ,12) ,12) ,4) ) +transpose(arpeggio(arpeggio(arpeggio((X+X) ) ) ) ,7) ) +(step(transpose(transpose(X,4) ,-5) ,12) +(X+transpose(X,7) ) ) ) ,4) ) ,-5) ,4,6) ,-5) ,7) ) +((((transpose(((echo(transpose(shuffle(echo(X,4,6) ) ,-5) ,4,6) +transpose((step(step(X,12) ,12) |echo(transpose(arpeggio(step(X,12) ) ,4) ,4,6) ) ,4) ) +transpose(arpeggio(transpose(arpeggio((X|X) ) ,-5) ) ,7) ) ,4) +transpose(step(arpeggio((transpose(transpose(transpose(step(shuffle(step(X,12) ) ,12) ,-5) ,-5) ,4) +transpose(arpeggio(transpose(arpeggio(echo(X,4,6) ) ,-5) ) ,7) ) ) ,12) ,7) ) +transpose(transpose((((((((transpose(transpose(shuffle(step(X,12) ) ,4) ,-5) +transpose(echo((X+transpose((X+transpose(X,7) ) ,12) ) ,4,6) ,4) ) +transpose(X,7) ) +transpose(shuffle(transpose(shuffle(((X+transpose(X,4) ) +transpose(transpose(X,4) ,7) ) ) ,-5) ) ,4) ) +transpose(transpose(((arpeggio(step(X,12) ) +transpose(transpose(X,-5) ,12) ) +transpose(arpeggio(X) ,4) ) ,-5) ,7) ) +transpose((transpose((shuffle(X) +transpose(X,-5) ) ,-7) +transpose(arpeggio(transpose(arpeggio(X) ,4) ) ,12) ) ,7) ) +transpose((((((step(echo((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(X,-5) ) ,4,6) ,12) |X) +transpose((arpeggio(echo((X+X) ,4,6) ) |echo(echo(X,4,6) ,4,6) ) ,4) ) +transpose(((((X+transpose(step(X,12) ,7) ) +transpose(X,4) ) +transpose(shuffle(shuffle(X) ) ,7) ) +step((shuffle(arpeggio(X) ) |echo((X+X) ,4,6) ) ,12) ) ,7) ) |transpose(((shuffle(X) +transpose(echo(X,4,6) ,4) ) +transpose(transpose(X,-5) ,7) ) ,-7) ) +transpose(((((transpose(X,-7) +echo(transpose(transpose(X,-5) ,-5) ,4,6) ) +transpose((echo(X,4,6) |shuffle(X) ) ,4) ) +transpose(transpose((transpose((X|X) ,4) +step(X,12) ) ,4) ,7) ) +shuffle(step(arpeggio(step(transpose(X,-5) ,12) ) ,12) ) ) ,7) ) ,4) ) +transpose(((transpose((X+transpose(shuffle(echo(X,4,6) ) ,12) ) ,-7) +transpose(arpeggio((X+transpose(X,12) ) ) ,4) ) +transpose(transpose(X,-5) ,7) ) ,7) ) ,-7) ,-5) ) +transpose(transpose(shuffle(((echo(((echo((transpose(X,-7) +X) ,4,6) +transpose((step(X,12) +((X+transpose(transpose(X,-7) ,12) ) |(X+transpose(X,7) ) ) ) ,4) ) +transpose(transpose((transpose(X,-7) |X) ,4) ,7) ) ,4,6) +transpose(transpose(shuffle(X) ,4) ,4) ) +transpose((echo(((X+transpose(transpose(transpose(X,-5) ,4) ,4) ) +transpose(((X+X) +transpose((X+transpose(X,12) ) ,7) ) ,7) ) ,4,6) +transpose((arpeggio(shuffle(X) ) +transpose(shuffle(((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(arpeggio(((X+transpose(X,4) ) +transpose(X,7) ) ) ,12) ) +step(transpose(X,4) ,12) ) ) ,12) ) ,12) ) ,7) ) ) ,4) ,4) ) +transpose(step(((((step(transpose((X+X) ,-5) ,12) +(shuffle(X) +transpose(X,12) ) ) +transpose(shuffle(transpose(((echo((X|X) ,4,6) +transpose(arpeggio(transpose(X,4) ) ,4) ) +transpose(echo(X,4,6) ,7) ) ,4) ) ,12) ) +transpose(step(((transpose((step((X+X) ,12) +(X+transpose(echo(X,4,6) ,4) ) ) ,4) +transpose((echo((arpeggio((X+X) ) +transpose((X+X) ,12) ) ,4,6) +shuffle(transpose(X,-5) ) ) ,4) ) +transpose(step(transpose(((shuffle(arpeggio(X) ) +transpose(transpose(X,-7) ,4) ) +transpose(echo(transpose(X,-7) ,4,6) ,7) ) ,-7) ,12) ,7) ) ,12) ,4) ) +transpose(echo(transpose((step(X,12) +transpose(shuffle(shuffle(X) ) ,12) ) ,-5) ,4,6) ,7) ) ,12) ,7) ) ) +(transpose(arpeggio(((echo(arpeggio(step(step(arpeggio(((transpose(X,-5) +transpose(X,4) ) +transpose((X+X) ,7) ) ) ,12) ,12) ) ,4,6) +transpose((transpose(((step(arpeggio(X) ,12) +transpose(((echo(X,4,6) +transpose(arpeggio(transpose(X,-5) ) ,4) ) +transpose(((shuffle(X) +transpose((X|X) ,4) ) +transpose(echo(X,4,6) ,7) ) ,7) ) ,4) ) +transpose((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(shuffle(arpeggio(X) ) ,7) ) ,7) ) ,-7) |arpeggio(transpose((((((echo(X,4,6) +transpose(shuffle((X|X) ) ,4) ) +transpose((((X+X) +transpose(X,4) ) +transpose((X+transpose(X,12) ) ,7) ) ,7) ) +transpose((X+transpose(X,12) ) ,-5) ) +transpose((X+transpose(step((X+transpose(X,7) ) ,12) ,7) ) ,4) ) +transpose((((((echo(X,4,6) +transpose(X,4) ) +transpose(step(X,12) ,7) ) +transpose(step(((X+transpose(X,4) ) +transpose(X,7) ) ,12) ,4) ) +transpose((echo(X,4,6) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,12) ) ,7) ) +transpose(transpose(echo(transpose(X,-5) ,4,6) ,4) ,12) ) ,7) ) ,-7) ) ) ,4) ) +transpose(arpeggio(((echo(X,4,6) +transpose(shuffle(arpeggio(((X+transpose(X,4) ) +transpose(X,7) ) ) ) ,4) ) +transpose(step(transpose(X,-7) ,12) ,7) ) ) ,7) ) ) ,4) |shuffle(transpose((transpose(echo(transpose(echo(X,4,6) ,-7) ,4,6) ,-5) +(shuffle((shuffle(X) |step(X,12) ) ) |arpeggio(X) ) ) ,-7) ) ) ) ,4,6)
random seed used was 131262057

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