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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Phrase for X:
# of Tracks:
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After 20 generations the expression "X" became this:
transpose(((shuffle(arpeggio(transpose(transpose(((((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(((step(X,12) +transpose((echo(X,4,6) +transpose(X,-5) ) ,12) ) |((transpose(X,4) +transpose(echo(X,4,6) ,4) ) +transpose(((transpose(X,-7) +transpose((X+transpose(X,12) ) ,12) ) +transpose(X,4) ) ,7) ) ) ,12) ) +transpose(transpose(step(echo((X+transpose(X,7) ) ,4,6) ,12) ,-5) ,4) ) +transpose(step(X,12) ,7) ) +step(echo(((X+(X+X) ) +echo((X|X) ,4,6) ) ,4,6) ,12) ) ,4) ,-5) ) ) +transpose(transpose(shuffle((((transpose(transpose(transpose((shuffle(transpose(transpose(X,-5) ,-7) ) |(transpose(X,4) +transpose(transpose(X,4) ,12) ) ) ,-7) ,-5) ,4) |transpose((transpose((X+transpose(X,7) ) ,4) +transpose(echo(step(transpose(echo(X,4,6) ,4) ,12) ,4,6) ,7) ) ,4) ) +transpose(((transpose(((X+X) +transpose((X|X) ,7) ) ,-5) +transpose(step(X,12) ,-7) ) +((step((X+X) ,12) +transpose(((X|X) +transpose((transpose(X,-5) +transpose(X,7) ) ,7) ) ,12) ) +transpose(((transpose(arpeggio((X+transpose(X,7) ) ) ,-7) +transpose(transpose(X,4) ,4) ) +transpose(transpose(shuffle(X) ,4) ,7) ) ,12) ) ) ,7) ) +transpose(((((echo(((X+X) |transpose(X,-5) ) ,4,6) +transpose(echo(echo(transpose(X,4) ,4,6) ,4,6) ,4) ) +transpose((transpose(shuffle((echo(transpose(X,-7) ,4,6) +transpose(transpose(X,-7) ,4) ) ) ,-7) |arpeggio(transpose(arpeggio(transpose(X,-5) ) ,4) ) ) ,7) ) +transpose(((echo((step(transpose(transpose(X,-5) ,-7) ,12) +(X+transpose(echo((X|X) ,4,6) ,-5) ) ) ,4,6) +transpose(((transpose((X+transpose((X+transpose(X,12) ) ,12) ) ,4) +transpose(transpose((X+X) ,4) ,12) ) +transpose(shuffle(transpose(X,-5) ) ,7) ) ,4) ) +transpose(transpose((echo(shuffle(step(transpose(X,4) ,12) ) ,4,6) |step((echo(transpose(transpose(X,-7) ,4) ,4,6) +transpose(step(transpose(X,-5) ,12) ,12) ) ,12) ) ,-7) ,7) ) ,4) ) +transpose(echo(arpeggio(transpose(arpeggio(shuffle(X) ) ,-7) ) ,4,6) ,7) ) ,7) ) ) ,4) ,7) ) +transpose(transpose(((((((echo(shuffle(transpose(shuffle(step(X,12) ) ,-5) ) ,4,6) +transpose(transpose(transpose((transpose(X,-7) |echo(X,4,6) ) ,-5) ,-5) ,-7) ) +((transpose((((transpose(X,-5) |transpose(transpose(arpeggio(X) ,-5) ,-7) ) +transpose((X+transpose(X,12) ) ,-7) ) +transpose(transpose(arpeggio(transpose((X+X) ,-7) ) ,-5) ,7) ) ,4) +((transpose((X+transpose((X+X) ,12) ) ,-5) +transpose(echo(X,4,6) ,7) ) +transpose(step(shuffle(X) ,12) ,7) ) ) |transpose(transpose((transpose((X+((X+transpose(X,12) ) +step(X,12) ) ) ,-7) |transpose(transpose(((transpose(X,4) +transpose(X,12) ) |((X+transpose(X,12) ) +(X+transpose(X,12) ) ) ) ,-7) ,-5) ) ,-7) ,4) ) ) +transpose((step((((arpeggio(echo((X|X) ,4,6) ) +transpose(((transpose(step(X,12) ,-7) +(shuffle(transpose(X,4) ) |transpose(X,4) ) ) |shuffle((echo(transpose(X,4) ,4,6) +((X|X) +(X+X) ) ) ) ) ,12) ) +transpose(shuffle((transpose(((X+X) +(X+transpose(X,7) ) ) ,-5) +shuffle(arpeggio(((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(echo(X,4,6) ,4) ) +transpose(X,7) ) ) ) ) ) ,7) ) +transpose(shuffle(transpose(arpeggio(((X+X) +transpose(X,4) ) ) ,-7) ) ,4) ) ,12) +((transpose(transpose(((transpose(arpeggio(arpeggio(X) ) ,-5) |transpose(transpose(step(transpose((X+transpose(X,7) ) ,4) ,12) ,-5) ,4) ) +transpose(((arpeggio(X) |((X+transpose(X,4) ) +transpose(X,7) ) ) +transpose((((transpose(X,-7) +transpose((X+transpose(X,12) ) ,4) ) +transpose((X+X) ,7) ) +shuffle(transpose(X,4) ) ) ,7) ) ,7) ) ,-7) ,4) +transpose((transpose(shuffle((arpeggio(transpose(transpose((X+transpose(X,12) ) ,-5) ,-7) ) +(((((X|X) |X) +transpose((X+transpose(X,12) ) ,4) ) +transpose(((X+transpose(X,12) ) |X) ,7) ) +transpose(((((X+transpose(X,4) ) +transpose(X,7) ) +transpose((X+transpose(X,12) ) ,7) ) |shuffle(transpose(X,-7) ) ) ,12) ) ) ) ,-7) +transpose(echo(transpose(transpose(((transpose(transpose(X,-5) ,4) |((X|X) +(echo(X,4,6) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) ) ) |transpose(echo((X+transpose(X,12) ) ,4,6) ,4) ) ,-7) ,-5) ,4,6) ,7) ) ,7) ) +transpose(transpose(((step(step(echo(transpose(X,-5) ,4,6) ,12) ,12) +(((transpose(shuffle(X) ,4) +transpose((X|X) ,4) ) +transpose(transpose((transpose(X,-5) +transpose(X,-7) ) ,4) ,7) ) |(((transpose(X,-5) +transpose(X,4) ) +transpose(transpose(arpeggio(X) ,-7) ,7) ) +echo((transpose((X|X) ,4) |X) ,4,6) ) ) ) |(echo(arpeggio(((echo(transpose(X,4) ,4,6) +transpose(echo(echo(X,4,6) ,4,6) ,7) ) +transpose(arpeggio(shuffle(X) ) ,-7) ) ) ,4,6) +((transpose(((transpose(X,4) +X) +(X+transpose(X,12) ) ) ,4) |arpeggio((transpose(X,4) |((X+transpose(X,4) ) +transpose(X,7) ) ) ) ) +transpose(arpeggio(transpose((X+((X|X) +transpose(X,12) ) ) ,-5) ) ,-5) ) ) ) ,-7) ,12) ) ) ,7) ) +transpose(transpose(((transpose((shuffle(transpose(transpose(X,4) ,4) ) +transpose(shuffle((transpose(X,-7) |shuffle(X) ) ) ,12) ) ,-5) +echo((echo((X+transpose(X,12) ) ,4,6) +transpose(((X+transpose(X,-7) ) +transpose((X|(X+X) ) ,12) ) ,-5) ) ,4,6) ) +transpose(((((transpose(((transpose(X,4) +echo(X,4,6) ) +step(transpose(transpose(X,-5) ,-5) ,12) ) ,-5) +transpose((arpeggio(((X+transpose(X,12) ) +X) ) |arpeggio(((echo(arpeggio(X) ,4,6) +transpose(((X|((X+transpose(X,4) ) +transpose(X,7) ) ) +transpose(X,-7) ) ,4) ) +transpose((transpose(shuffle(X) ,-5) |(X+transpose(X,7) ) ) ,7) ) ) ) ,4) ) +transpose(((((X+transpose(transpose((X+X) ,4) ,7) ) |arpeggio(arpeggio(step(X,12) ) ) ) +transpose(transpose(X,-5) ,12) ) +transpose((transpose(transpose(X,-5) ,-5) +shuffle((((X+transpose((X|X) ,4) ) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) +transpose(X,12) ) ) ) ,7) ) ,7) ) +transpose(transpose(echo(step((echo(X,4,6) +(X+transpose((X+X) ,7) ) ) ,12) ,4,6) ,4) ,4) ) +transpose(transpose(((transpose((((X+transpose(X,4) ) +transpose(X,7) ) +(X+transpose(X,7) ) ) ,-5) +transpose((transpose(X,4) +(X+X) ) ,7) ) +transpose(transpose(X,4) ,4) ) ,4) ,7) ) ,-5) ) ,-7) ,4) ) +transpose((((((shuffle(arpeggio(((((X+transpose(X,4) ) +transpose(X,7) ) +step(X,12) ) +transpose(arpeggio((X+transpose(X,12) ) ) ,7) ) ) ) +(arpeggio(shuffle((transpose((transpose(X,-5) +transpose((X+transpose(X,12) ) ,4) ) ,-7) +echo(transpose((X+X) ,4) ,4,6) ) ) ) +transpose((transpose(transpose(X,4) ,-7) +transpose(transpose(transpose((X|X) ,-5) ,-7) ,7) ) ,7) ) ) |(transpose(echo((transpose(X,4) +transpose(X,12) ) ,4,6) ,4) +echo((shuffle((arpeggio(step(X,12) ) |transpose(transpose(X,-7) ,-7) ) ) |transpose((((transpose(X,4) |transpose(((X+X) +(X|X) ) ,-5) ) +transpose(((X+transpose((X|X) ,7) ) |((X+transpose(X,7) ) +((transpose(X,4) +transpose((X+transpose(X,12) ) ,4) ) +transpose(X,7) ) ) ) ,4) ) +transpose((transpose(X,4) +transpose(transpose(X,-7) ,12) ) ,7) ) ,-7) ) ,4,6) ) ) +transpose(transpose(((((((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(X,4) ) +transpose(step(X,12) ,7) ) |(X+transpose(X,12) ) ) |transpose(step(shuffle(X) ,12) ,-7) ) +transpose(echo((transpose(X,4) +transpose((transpose((X+transpose(X,12) ) ,-7) |transpose(X,-7) ) ,12) ) ,4,6) ,12) ) +((echo(((transpose(X,-7) +transpose(X,7) ) +transpose(arpeggio(X) ,12) ) ,4,6) +step(transpose(X,-7) ,12) ) +step(transpose(transpose(X,-5) ,-7) ,12) ) ) ,-7) ,4) ) +transpose(transpose(step(arpeggio((X+transpose(X,7) ) ) ,12) ,-5) ,7) ) +transpose(transpose(X,-7) ,12) ) ,7) ) +transpose(arpeggio(((transpose(((X+transpose(transpose((((echo(X,4,6) +(transpose(X,4) +X) ) +transpose(transpose((transpose(X,-5) +transpose(X,-5) ) ,4) ,4) ) +transpose(transpose(transpose(transpose(X,-7) ,-7) ,-5) ,7) ) ,-5) ,4) ) +transpose(transpose(step(shuffle((X+transpose(X,12) ) ) ,12) ,-5) ,7) ) ,-5) +transpose(((transpose(transpose(step(((X+X) +(X+X) ) ,12) ,-7) ,-5) +transpose(transpose(transpose(shuffle((shuffle(X) +transpose(echo(X,4,6) ,7) ) ) ,4) ,4) ,4) ) +transpose(transpose(((X+transpose(transpose(shuffle(X) ,-7) ,4) ) +transpose(((X+transpose((X+transpose(X,7) ) ,4) ) +transpose(X,7) ) ,7) ) ,-7) ,7) ) ,7) ) |(((transpose((transpose((step(transpose(X,-5) ,12) +(shuffle(X) +transpose(X,-5) ) ) ,-5) +arpeggio((((arpeggio(echo(X,4,6) ) +transpose(((X+transpose(X,12) ) +transpose(X,12) ) ,12) ) +transpose(transpose((X+transpose(X,7) ) ,4) ,4) ) +transpose((echo((((X+transpose(X,4) ) +transpose(X,7) ) |transpose((X|X) ,4) ) ,4,6) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-7) ) ,12) ) ) ) ,-5) +(shuffle(((transpose((X+X) ,-7) +transpose((X|X) ,4) ) +arpeggio((((step(transpose(X,-7) ,12) +X) +transpose(transpose(transpose((X+transpose(X,12) ) ,4) ,4) ,4) ) +transpose(step(transpose(X,4) ,12) ,7) ) ) ) ) +transpose((step((X+transpose(X,7) ) ,12) |step(transpose(transpose(X,-7) ,-5) ,12) ) ,7) ) ) +transpose(echo(shuffle((((echo(X,4,6) |X) |step(X,12) ) |transpose(X,4) ) ) ,4,6) ,4) ) +transpose(transpose(transpose(transpose((transpose(X,-5) |X) ,4) ,-7) ,-7) ,7) ) ) ) ,7) ) ,4) ,7) ) ,4)
random seed used was 3621130

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