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((arpeggio(step(echo((transpose(shuffle((echo((transpose((X|X) ,4) +step(X,12) ) ,4,6) |arpeggio((echo(X,4,6) +transpose(transpose(X,4) ,7) ) ) ) ) ,-5) |arpeggio((echo((X|((X+transpose(X,4) ) +transpose(X,7) ) ) ,4,6) |echo(((X+transpose((X+transpose(X,7) ) ,4) ) +transpose(arpeggio(echo(X,4,6) ) ,7) ) ,4,6) ) ) ) ,4,6) ,12) ) |(((step(arpeggio(shuffle(transpose(step((((X+X) +X) +transpose(X,12) ) ,12) ,-5) ) ) ,12) +transpose(transpose(transpose((arpeggio(((step((((X+transpose(X,4) ) +transpose(X,7) ) +X) ,12) +transpose(((shuffle(X) +transpose((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(arpeggio(X) ,12) ) ,4) ) +transpose(echo(X,4,6) ,7) ) ,4) ) +transpose((X|X) ,7) ) ) +transpose(((echo(step((X+transpose(X,12) ) ,12) ,4,6) +transpose((X+transpose(((X+transpose(X,12) ) +transpose(X,-7) ) ,7) ) ,4) ) +transpose(transpose(transpose(echo(transpose(X,-7) ,4,6) ,-5) ,-7) ,7) ) ,12) ) ,-7) ,4) ,12) ) +transpose(transpose((((arpeggio(((((((shuffle(X) +transpose(step(X,12) ,4) ) +transpose((X|X) ,7) ) +transpose(arpeggio((echo(X,4,6) +transpose(echo(X,4,6) ,12) ) ) ,7) ) +transpose(shuffle(transpose(shuffle(shuffle(X) ) ,-5) ) ,4) ) +transpose((arpeggio(X) |step(echo(X,4,6) ,12) ) ,7) ) +echo((((X|X) +transpose(arpeggio(transpose(X,-7) ) ,4) ) +transpose((echo(echo(X,4,6) ,4,6) +step(X,12) ) ,7) ) ,4,6) ) ) +step(echo(((transpose(step(X,12) ,4) +transpose(((X+transpose(arpeggio(transpose(X,-7) ) ,4) ) +transpose(transpose(X,-7) ,7) ) ,4) ) +transpose(transpose((shuffle((X+X) ) |((transpose(X,-7) +transpose(X,4) ) +transpose((X+X) ,7) ) ) ,-5) ,7) ) ,4,6) ,12) ) +transpose(((transpose(shuffle((step((transpose((X+X) ,-7) +transpose(transpose(X,-5) ,12) ) ,12) +transpose(echo(X,4,6) ,-5) ) ) ,4) +transpose(echo(shuffle((transpose((((X+transpose(X,7) ) +transpose(transpose(X,4) ,4) ) +transpose(X,7) ) ,-7) +transpose(transpose(shuffle(arpeggio((X+transpose(X,12) ) ) ) ,-7) ,7) ) ) ,4,6) ,12) ) |(arpeggio(step(X,12) ) |transpose(((transpose(shuffle((shuffle(X) +X) ) ,-5) +transpose(transpose((step(X,12) |transpose((X+X) ,4) ) ,-7) ,4) ) +transpose(((shuffle(X) +transpose(X,4) ) +transpose(transpose(X,-7) ,7) ) ,7) ) ,4) ) ) ,4) ) +transpose(((transpose(step(shuffle(shuffle((X+X) ) ) ,12) ,-7) +transpose(step(step(X,12) ,12) ,7) ) +((transpose(transpose(X,4) ,-7) +transpose(shuffle(step(((step(echo(X,4,6) ,12) +transpose(arpeggio(transpose(X,-5) ) ,4) ) +transpose(echo(X,4,6) ,7) ) ,12) ) ,4) ) +transpose(transpose((((((X+transpose(X,12) ) +transpose((X+transpose(X,12) ) ,4) ) +transpose(X,7) ) |transpose(((X+transpose(X,12) ) |transpose(X,-5) ) ,4) ) +transpose(step(step(X,12) ,12) ,4) ) ,-7) ,7) ) ) ,7) ) ,4) ,12) ) |(((step((echo(step(step(transpose(transpose(transpose((X|(((X+transpose(X,4) ) +transpose(X,7) ) +(X|X) ) ) ,4) ,-7) ,4) ,12) ,12) ,4,6) |shuffle((step((((shuffle(transpose(arpeggio(X) ,4) ) +arpeggio((X+transpose(X,7) ) ) ) +transpose((((arpeggio(step(X,12) ) +transpose((X+transpose(X,-5) ) ,12) ) +transpose((arpeggio(step(X,12) ) |X) ,4) ) +transpose(shuffle((arpeggio(X) |step(step(X,12) ,12) ) ) ,7) ) ,4) ) +transpose(step(((transpose(X,-5) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) ) +transpose(shuffle(X) ,7) ) ,12) ,7) ) ,12) |((step((((arpeggio(X) +transpose((X|X) ,7) ) +transpose((((X+transpose(X,4) ) +transpose(echo(X,4,6) ,7) ) |(step(X,12) +((X+transpose(X,4) ) +transpose(X,7) ) ) ) ,4) ) +transpose(echo(((X+transpose(X,4) ) +transpose(X,7) ) ,4,6) ,7) ) ,12) +transpose(((echo(echo(X,4,6) ,4,6) +shuffle((X+transpose(X,12) ) ) ) +transpose(arpeggio(transpose(transpose(X,-5) ,-5) ) ,12) ) ,4) ) +transpose(transpose(step(X,12) ,-5) ,7) ) ) ) ) ,12) +arpeggio((transpose((((shuffle(X) +transpose(step(X,12) ,7) ) +transpose(arpeggio(X) ,4) ) +transpose(X,7) ) ,-5) |(((transpose(X,-7) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,12) ) +((X+transpose(X,4) ) |((X+transpose(X,4) ) +transpose(X,7) ) ) ) |(step(step((shuffle((echo(X,4,6) |shuffle(X) ) ) |transpose(X,4) ) ,12) ,12) +step(shuffle(((X|X) +((shuffle(transpose(X,-5) ) +transpose(transpose(arpeggio(X) ,-5) ,4) ) +transpose((X+X) ,7) ) ) ) ,12) ) ) ) ) ) +transpose(arpeggio((transpose(transpose((((echo(step(X,12) ,4,6) +transpose(step(X,12) ,4) ) +transpose(step((X+X) ,12) ,7) ) +transpose(transpose(X,-7) ,7) ) ,4) ,4) +transpose(echo((((transpose(step(X,12) ,4) +transpose((arpeggio(arpeggio(step(X,12) ) ) +transpose(shuffle(((X+transpose(arpeggio((X|X) ) ,4) ) +transpose(X,7) ) ) ,7) ) ,4) ) +transpose(arpeggio((((shuffle(transpose(arpeggio(X) ,4) ) |step((transpose(X,-7) |X) ,12) ) +transpose(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-5) ,4) ) +transpose(((echo(step(X,12) ,4,6) +transpose(shuffle(X) ,4) ) +transpose(shuffle(X) ,7) ) ,7) ) ) ,7) ) +transpose(transpose(transpose(((X+transpose((X+transpose(X,7) ) ,4) ) +transpose(X,7) ) ,-7) ,4) ,12) ) ,4,6) ,7) ) ) ,4) ) +transpose(transpose((arpeggio(echo(shuffle(shuffle((arpeggio((((X+transpose(X,12) ) +transpose(arpeggio(X) ,4) ) +transpose((X+transpose(X,12) ) ,7) ) ) +(X+transpose(X,12) ) ) ) ) ,4,6) ) +transpose(transpose(shuffle(transpose(echo(echo(arpeggio(transpose(transpose(shuffle((X|X) ) ,4) ,4) ) ,4,6) ,4,6) ,4) ) ,-7) ,12) ) ,4) ,7) ) ) ) ,-5) +transpose(transpose(transpose((transpose(shuffle(transpose(transpose(arpeggio(shuffle(X) ) ,-5) ,-7) ) ,4) +transpose((((arpeggio(transpose(((transpose((arpeggio(((echo(X,4,6) +transpose((transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-5) +transpose(X,7) ) ,4) ) +transpose(shuffle(X) ,7) ) ) |((X+transpose(arpeggio(X) ,4) ) +transpose(arpeggio(X) ,7) ) ) ,-7) +transpose((arpeggio(arpeggio(transpose(((arpeggio(X) +transpose(step((X+transpose(X,12) ) ,12) ,4) ) +transpose(echo(((X+transpose(X,4) ) +transpose(X,7) ) ,4,6) ,7) ) ,-7) ) ) +((shuffle(X) +transpose(arpeggio((arpeggio((transpose(X,4) +X) ) +transpose(echo(X,4,6) ,12) ) ) ,4) ) +transpose(echo(transpose((X+X) ,-7) ,4,6) ,7) ) ) ,4) ) +transpose(((step(((X+(X|X) ) +transpose(X,-7) ) ,12) +shuffle((step((arpeggio(X) |X) ,12) |transpose(step(((X+transpose(X,4) ) +transpose(X,7) ) ,12) ,-5) ) ) ) +transpose(transpose(((transpose(((((((X|X) +transpose(shuffle(X) ,4) ) +transpose(X,7) ) |shuffle(X) ) +transpose(arpeggio(X) ,4) ) +transpose((arpeggio(((X+transpose(X,4) ) +transpose(X,7) ) ) +transpose(((X+transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) ) +transpose(X,7) ) ,7) ) ,7) ) ,-5) +transpose(((transpose(transpose(X,4) ,-5) |echo((X+transpose(X,12) ) ,4,6) ) +transpose(step((X+transpose(X,12) ) ,12) ,4) ) ,4) ) +transpose(echo(shuffle(step(X,12) ) ,4,6) ,7) ) ,4) ,12) ) ,7) ) ,4) ) +transpose((transpose((echo((step((transpose(arpeggio(X) ,-7) +transpose(step(transpose(X,4) ,12) ,7) ) ,12) +transpose((((transpose(transpose(X,-7) ,4) +echo(((arpeggio(X) +transpose((X+transpose(X,12) ) ,4) ) +transpose((X|X) ,7) ) ,4,6) ) +transpose(shuffle(X) ,12) ) +step(shuffle(arpeggio(transpose(X,4) ) ) ,12) ) ,7) ) ,4,6) |transpose(shuffle(transpose(X,4) ) ,-5) ) ,4) |(((((((X+transpose(shuffle(X) ,7) ) +transpose(transpose((X+X) ,-7) ,4) ) +transpose(echo((X+X) ,4,6) ,7) ) |(arpeggio((transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-7) +shuffle(transpose(X,-5) ) ) ) +transpose((shuffle((((X+transpose(X,12) ) +transpose((X|X) ,4) ) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) ) +transpose(echo(shuffle(((X|X) |shuffle(((X+transpose(X,4) ) +transpose(X,7) ) ) ) ) ,4,6) ,7) ) ,12) ) ) +(transpose((((((shuffle(shuffle(transpose(X,-7) ) ) +transpose((((X+transpose(step(X,12) ,7) ) +transpose(X,4) ) +transpose((X+X) ,7) ) ,4) ) +transpose((((X|X) +transpose(X,4) ) +transpose((echo(X,4,6) |transpose(X,-7) ) ,7) ) ,7) ) +transpose(transpose(echo((X+transpose(X,12) ) ,4,6) ,-5) ,4) ) +transpose((transpose(((((X|X) +transpose(transpose(X,-7) ,7) ) +transpose(echo(X,4,6) ,4) ) +transpose((echo(X,4,6) +transpose(X,7) ) ,7) ) ,4) +transpose((((((X+transpose(X,4) ) +transpose(X,7) ) +(X+transpose(X,7) ) ) +transpose(X,4) ) +transpose((transpose(echo(X,4,6) ,-5) +X) ,7) ) ,7) ) ,4) ) +transpose(((((transpose((X|X) ,-5) +transpose(transpose(X,-7) ,4) ) +transpose(echo((X+transpose(X,12) ) ,4,6) ,7) ) +transpose(transpose(transpose(echo(X,4,6) ,-7) ,-5) ,4) ) +transpose(step(X,12) ,7) ) ,7) ) ,-5) +transpose(arpeggio((((((step(X,12) +transpose(((echo(X,4,6) +arpeggio(X) ) +transpose(shuffle(X) ,12) ) ,4) ) +transpose(echo((((X+transpose(X,7) ) +transpose(transpose(X,4) ,4) ) +transpose(transpose(X,-7) ,7) ) ,4,6) ,7) ) +transpose(step(arpeggio(shuffle(X) ) ,12) ,12) ) +transpose(((((echo((step(X,12) +arpeggio(X) ) ,4,6) +transpose(shuffle(((X+transpose(X,4) ) +transpose(X,7) ) ) ,4) ) +transpose((shuffle(echo(shuffle(X) ,4,6) ) +((step(X,12) +transpose((X+X) ,4) ) +transpose(step(X,12) ,7) ) ) ,7) ) +transpose(echo(echo(shuffle(X) ,4,6) ,4,6) ,4) ) +transpose(step((transpose(X,4) |(X|(X|X) ) ) ,12) ,7) ) ,4) ) +transpose(arpeggio(transpose(((transpose(shuffle(X) ,4) |((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(X,4) ) +transpose(transpose(X,-5) ,7) ) ) |((arpeggio(X) +transpose(X,4) ) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) ) ,4) ) ,7) ) ) ,12) ) ) +transpose(step(((((shuffle(arpeggio(arpeggio(X) ) ) +transpose(step(arpeggio(X) ,12) ,4) ) +transpose(transpose(step(X,12) ,4) ,7) ) +transpose(arpeggio(step(transpose(X,-5) ,12) ) ,4) ) +transpose(((shuffle(X) +X) +transpose((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(shuffle(arpeggio(X) ) ,12) ) ,7) ) ,7) ) ,12) ,4) ) +transpose((((((echo(arpeggio((shuffle(arpeggio(X) ) +transpose((transpose(X,4) |((X+transpose(X,4) ) +transpose(X,7) ) ) ,12) ) ) ,4,6) +transpose(((arpeggio(step(((X+transpose(X,4) ) +transpose(X,7) ) ,12) ) +transpose(transpose(transpose(shuffle(X) ,-5) ,-5) ,4) ) +transpose(arpeggio(shuffle(transpose(X,-7) ) ) ,7) ) ,4) ) +transpose(((X+transpose(X,12) ) +X) ,7) ) +transpose(((((step((X+transpose(X,12) ) ,12) +transpose(X,4) ) |((transpose(((((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(shuffle(X) ,4) ) +transpose((X|X) ,7) ) +transpose(((transpose(X,-7) +transpose((X|X) ,4) ) +transpose((((X|X) +transpose(X,4) ) +transpose(X,7) ) ,7) ) ,4) ) +transpose((step(X,12) +transpose(shuffle(X) ,4) ) ,7) ) ,4) +transpose(transpose(transpose(echo((echo(X,4,6) +(X+X) ) ,4,6) ,4) ,-5) ,4) ) +transpose(transpose(echo(X,4,6) ,-7) ,7) ) ) +transpose(((echo(arpeggio((step(X,12) +transpose(((arpeggio(X) +transpose(X,12) ) +transpose(shuffle(((X+transpose(X,4) ) +transpose(X,7) ) ) ,12) ) ,12) ) ) ,4,6) +transpose(transpose(transpose((((X+transpose(X,4) ) +transpose(X,7) ) |transpose(X,4) ) ,4) ,4) ,4) ) +transpose(step(transpose(echo(transpose(X,4) ,4,6) ,-7) ,12) ,7) ) ,4) ) +transpose(shuffle(transpose((((X|X) +transpose(X,12) ) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-7) ) ,-7) ) ,7) ) ,7) ) +transpose(shuffle(shuffle(arpeggio(echo(X,4,6) ) ) ) ,4) ) +transpose(transpose((((arpeggio((((X+transpose(X,12) ) +transpose(transpose((X+X) ,-7) ,4) ) +transpose(transpose(shuffle((X|X) ) ,-5) ,7) ) ) |echo(((X+transpose(transpose(X,4) ,4) ) +transpose(step(((((X+transpose((X+X) ,4) ) +transpose(X,7) ) +transpose((transpose(X,-5) +transpose(X,4) ) ,4) ) +transpose(transpose(shuffle(X) ,-5) ,7) ) ,12) ,12) ) ,4,6) ) +transpose((((((X|transpose(X,-7) ) +transpose(X,4) ) +transpose(transpose(X,-5) ,7) ) |(echo(echo(step(X,12) ,4,6) ,4,6) +transpose(((X+transpose(X,12) ) +transpose(X,4) ) ,7) ) ) +transpose(transpose(transpose(shuffle(echo(X,4,6) ) ,4) ,-5) ,12) ) ,4) ) +transpose(arpeggio(transpose(echo(arpeggio(X) ,4,6) ,-7) ) ,7) ) ,-5) ,7) ) ,7) ) ) ,4) ) +transpose((((echo(((echo(((echo((((arpeggio(X) +X) +transpose((arpeggio(X) |((X+transpose(X,4) ) +transpose(X,7) ) ) ,4) ) +transpose(step((X|X) ,12) ,7) ) ,4,6) +transpose(transpose(echo(shuffle(X) ,4,6) ,-7) ,4) ) +transpose((shuffle(((X+transpose(X,4) ) +transpose(X,7) ) ) +transpose(echo(shuffle(((X+transpose(X,4) ) +transpose(X,7) ) ) ,4,6) ,7) ) ,7) ) ,4,6) +transpose((transpose((transpose(X,-5) +step(X,12) ) ,4) +transpose(echo(echo(X,4,6) ,4,6) ,-7) ) ,12) ) +(((((arpeggio((X|X) ) +transpose(((X+transpose(echo(X,4,6) ,4) ) +transpose(transpose(X,-7) ,7) ) ,7) ) +transpose(transpose(transpose(X,4) ,4) ,12) ) +transpose(echo(arpeggio((X+X) ) ,4,6) ,7) ) +transpose(step(echo((echo(step(echo(X,4,6) ,12) ,4,6) |transpose(X,4) ) ,4,6) ,12) ,4) ) +transpose(transpose(arpeggio((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(X,12) ) ) ,-5) ,7) ) ) ,4,6) +transpose((step((transpose(echo(X,4,6) ,-7) +transpose(echo(echo(((transpose(X,-5) +transpose(X,4) ) +transpose(transpose(X,4) ,7) ) ,4,6) ,4,6) ,7) ) ,12) |(transpose(arpeggio(((X+transpose(X,4) ) +transpose(X,7) ) ) ,-5) +(((X+transpose(X,4) ) +transpose(echo(X,4,6) ,7) ) |(step(X,12) |((X+transpose(X,4) ) +transpose(X,7) ) ) ) ) ) ,4) ) +transpose(shuffle((shuffle(transpose(shuffle((X+transpose(X,7) ) ) ,4) ) +transpose(transpose(transpose(echo((arpeggio(echo(shuffle(X) ,4,6) ) |step(transpose(X,-5) ,12) ) ,4,6) ,4) ,4) ,7) ) ) ,7) ) +transpose(shuffle((((shuffle(step(X,12) ) +transpose(echo(shuffle(arpeggio(X) ) ,4,6) ,12) ) +transpose((shuffle(transpose(((X+X) |(X+X) ) ,4) ) +transpose(transpose((X+X) ,4) ,7) ) ,4) ) +transpose(((step((X+transpose(X,7) ) ,12) +transpose(arpeggio(echo((((X+transpose(X,4) ) +transpose(X,7) ) +X) ,4,6) ) ,4) ) +transpose(transpose(transpose((X+transpose(echo(X,4,6) ,12) ) ,-5) ,-7) ,7) ) ,7) ) ) ,4) ) ,7) ) |transpose(echo(step(transpose(arpeggio((transpose(((echo(X,4,6) +shuffle(X) ) |X) ,-5) +transpose(arpeggio(transpose(arpeggio(X) ,4) ) ,12) ) ) ,-5) ,12) ,4,6) ,4) ) ,12) ) ,-5) ,4) ,7) )
random seed used was 241572845

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