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:
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After 18 generations the expression "X" became this:
((((((shuffle((step(transpose(transpose(X,4) ,4) ,12) +transpose(echo(((X+transpose(X,12) ) +transpose(transpose((X+X) ,4) ,7) ) ,4,6) ,7) ) ) +transpose(step((((echo((((shuffle(((transpose(X,-7) +transpose((X+X) ,4) ) +transpose(echo(((X+transpose(X,4) ) +transpose(X,7) ) ,4,6) ,7) ) ) |(echo(shuffle(X) ,4,6) |(echo(shuffle(X) ,4,6) +transpose(shuffle(X) ,7) ) ) ) +(X+X) ) +transpose(((echo(echo(echo(X,4,6) ,4,6) ,4,6) +transpose(X,12) ) +transpose(((arpeggio(X) +transpose(transpose(arpeggio(X) ,4) ,4) ) +transpose((transpose(X,4) +transpose((step(echo(X,4,6) ,12) +transpose(X,4) ) ,12) ) ,7) ) ,7) ) ,-7) ) ,4,6) +transpose(arpeggio(transpose((echo(arpeggio(echo(X,4,6) ) ,4,6) |transpose(arpeggio((transpose(X,4) |shuffle(X) ) ) ,4) ) ,-7) ) ,4) ) +transpose(shuffle(echo(((echo((transpose(X,4) +transpose(X,-7) ) ,4,6) +(transpose(echo(X,4,6) ,4) +transpose(transpose((X+transpose(X,12) ) ,-7) ,7) ) ) |step(X,12) ) ,4,6) ) ,7) ) |transpose(transpose(shuffle((transpose((((transpose(step(transpose(X,-5) ,12) ,-5) +arpeggio(X) ) +transpose(shuffle(step((X|X) ,12) ) ,4) ) +transpose((((echo(X,4,6) +transpose(echo(X,4,6) ,12) ) +transpose(echo((X+X) ,4,6) ,4) ) +transpose(step(X,12) ,7) ) ,7) ) ,-5) +transpose(((((((shuffle(arpeggio(X) ) +transpose((echo(X,4,6) +step(step(X,12) ,12) ) ,4) ) +transpose((transpose(shuffle(X) ,-7) +arpeggio(X) ) ,7) ) +transpose(step((X|shuffle(X) ) ,12) ,4) ) +transpose((shuffle(step(echo(X,4,6) ,12) ) +transpose(transpose((arpeggio(X) +X) ,4) ,12) ) ,7) ) +transpose(transpose(X,4) ,4) ) +transpose((((X+X) |transpose((X+X) ,-5) ) +transpose((X+transpose(X,12) ) ,-5) ) ,7) ) ,7) ) ) ,-7) ,4) ) ,12) ,-5) ) +transpose(transpose(arpeggio(shuffle(transpose((step((X|transpose(X,-7) ) ,12) +transpose(transpose((X+X) ,4) ,12) ) ,-5) ) ) ,-5) ,4) ) +transpose(step(echo((echo((transpose(arpeggio(step(transpose(X,4) ,12) ) ,-7) +transpose((shuffle(transpose(X,-7) ) +transpose((transpose(X,4) |((X+transpose(X,4) ) +transpose(X,7) ) ) ,-7) ) ,12) ) ,4,6) |(((transpose(transpose(X,4) ,4) +transpose(((transpose(step(X,12) ,-7) +transpose(arpeggio((X+transpose(X,7) ) ) ,4) ) +transpose(transpose(shuffle(X) ,-7) ,7) ) ,4) ) +transpose(shuffle(echo(((transpose(X,4) +transpose(shuffle(X) ,4) ) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) ,4,6) ) ,7) ) +transpose(echo(shuffle((arpeggio(step(X,12) ) |shuffle(transpose(((X+transpose((X+transpose(X,7) ) ,4) ) +transpose(echo(X,4,6) ,7) ) ,-7) ) ) ) ,4,6) ,12) ) ) ,4,6) ,12) ,7) ) |arpeggio((((((((transpose(((transpose(transpose(arpeggio((X+transpose(X,7) ) ) ,4) ,-7) +transpose((transpose((X+transpose(step(X,12) ,7) ) ,-7) |((transpose(((X+X) |arpeggio(X) ) ,-7) +transpose((((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(shuffle(X) ,4) ) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) +X) ,4) ) +transpose(echo(((shuffle(X) +transpose(X,4) ) +transpose(transpose(X,-7) ,7) ) ,4,6) ,7) ) ) ,4) ) +transpose(X,7) ) ,4) +transpose(step(transpose(transpose(step(transpose(((transpose(arpeggio(X) ,4) +transpose(((X|X) +transpose((X|X) ,7) ) ,4) ) +transpose(arpeggio(echo(X,4,6) ) ,7) ) ,-7) ,12) ,4) ,-5) ,12) ,4) ) +transpose(step(echo((echo(arpeggio((X|(transpose(X,-7) +transpose(transpose(X,4) ,12) ) ) ) ,4,6) |(((echo(arpeggio(transpose(X,-5) ) ,4,6) |((step(X,12) +transpose(transpose(transpose(X,-7) ,-7) ,4) ) +transpose(arpeggio(((X+transpose(X,4) ) +transpose(X,7) ) ) ,7) ) ) +transpose((echo(shuffle(shuffle(X) ) ,4,6) +step(((X+transpose(X,4) ) +transpose(X,7) ) ,12) ) ,4) ) +transpose(((shuffle(X) |((X+transpose(X,4) ) +transpose(X,7) ) ) +transpose(transpose(((X+X) |X) ,-5) ,7) ) ,7) ) ) ,4,6) ,12) ,7) ) +transpose((step(((shuffle((arpeggio((((X+X) +transpose(transpose(X,-7) ,4) ) +transpose(X,7) ) ) +transpose(arpeggio(step(X,12) ) ,7) ) ) |((transpose(transpose(X,4) ,4) +transpose(transpose(shuffle(X) ,4) ,12) ) |step(echo(X,4,6) ,12) ) ) |(echo(echo(step(X,12) ,4,6) ,4,6) +transpose(((arpeggio(arpeggio((shuffle(X) +arpeggio((X+X) ) ) ) ) +transpose(shuffle(transpose(shuffle((X+transpose(X,7) ) ) ,4) ) ,4) ) +transpose(((X+transpose((X+arpeggio(X) ) ,4) ) +transpose((X+transpose(X,7) ) ,7) ) ,7) ) ,12) ) ) ,12) |transpose((transpose((((X|X) +transpose(X,4) ) +transpose(echo(X,4,6) ,7) ) ,-5) |X) ,4) ) ,4) ) +transpose(step(step(arpeggio(arpeggio(step(transpose(((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(shuffle(X) ,4) ) +transpose(X,7) ) ,-7) ,12) ) ) ,12) ,12) ,7) ) +step((transpose(arpeggio(echo(echo(shuffle(transpose(X,-7) ) ,4,6) ,4,6) ) ,4) +transpose(shuffle(transpose(echo(((echo(transpose(echo((X+transpose(X,12) ) ,4,6) ,-7) ,4,6) +transpose(((transpose((X+X) ,4) |X) +transpose(step(shuffle((X|X) ) ,12) ,7) ) ,4) ) +transpose((echo(echo(echo(X,4,6) ,4,6) ,4,6) +shuffle(arpeggio(X) ) ) ,7) ) ,4,6) ,4) ) ,12) ) ,12) ) +transpose(shuffle((step((transpose(arpeggio((arpeggio(((X|X) +step(X,12) ) ) |arpeggio(((step(X,12) +transpose(transpose(X,4) ,4) ) +transpose(X,7) ) ) ) ) ,-5) +((arpeggio(arpeggio(transpose(X,4) ) ) +transpose((((((((arpeggio(X) +X) +transpose(arpeggio(X) ,7) ) +transpose(step(((X+transpose(X,4) ) +transpose(X,7) ) ,12) ,12) ) +transpose(X,4) ) +transpose(echo(((echo(X,4,6) +transpose((((X+transpose(X,12) ) +transpose(X,4) ) +transpose(X,7) ) ,4) ) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) ,4,6) ,7) ) +transpose(transpose(transpose((((X+transpose(X,7) ) +transpose(((X+transpose(X,4) ) +transpose(arpeggio(X) ,7) ) ,12) ) +transpose(transpose(shuffle(X) ,-5) ,7) ) ,4) ,4) ,4) ) +transpose(step(transpose(transpose(step(X,12) ,-7) ,4) ,12) ,7) ) ,4) ) +transpose(transpose(((X+transpose(X,7) ) |((X+transpose(X,4) ) +transpose(X,7) ) ) ,-7) ,7) ) ) ,12) +transpose(((step((arpeggio(((step((X|X) ,12) +transpose(arpeggio(X) ,7) ) +X) ) +echo(arpeggio(echo(((X+transpose((X+transpose(X,7) ) ,4) ) +transpose((X|X) ,7) ) ,4,6) ) ,4,6) ) ,12) +transpose((echo((transpose((((X+transpose(X,4) ) +transpose(X,7) ) +(X+X) ) ,-5) +transpose(((arpeggio(echo((echo(X,4,6) |X) ,4,6) ) +transpose(echo(X,4,6) ,4) ) +transpose(echo(shuffle(step(arpeggio(X) ,12) ) ,4,6) ,7) ) ,7) ) ,4,6) +transpose(shuffle(transpose(((echo(X,4,6) +echo(shuffle(X) ,4,6) ) |((arpeggio(X) +transpose(X,4) ) +transpose(X,7) ) ) ,4) ) ,7) ) ,4) ) +transpose(arpeggio((echo(((X+transpose(X,4) ) +transpose(X,7) ) ,4,6) |(((transpose(transpose(shuffle(echo(X,4,6) ) ,-7) ,-5) +transpose((step(transpose(X,-7) ,12) +((((arpeggio(X) +transpose(X,4) ) +transpose(X,7) ) +transpose(step(X,12) ,4) ) +transpose(X,7) ) ) ,4) ) +transpose((((arpeggio(((X+transpose(X,4) ) +transpose(X,7) ) ) +((X+transpose(transpose(X,-7) ,4) ) +transpose(X,7) ) ) +transpose(step((X|X) ,12) ,4) ) +transpose((X+(X+transpose(X,7) ) ) ,7) ) ,7) ) +transpose(step((transpose(arpeggio((X|X) ) ,-5) +step(X,12) ) ,12) ,7) ) ) ) ,7) ) ,12) ) ) ,4) ) +transpose((transpose(echo(transpose(echo(transpose(transpose(echo(step(X,12) ,4,6) ,-5) ,4) ,4,6) ,-5) ,4,6) ,4) |step((transpose(echo(shuffle(echo(step(transpose(arpeggio(X) ,-7) ,12) ,4,6) ) ,4,6) ,-5) |step(arpeggio(transpose((((X|X) +transpose(step(X,12) ,4) ) +transpose((arpeggio(step(X,12) ) +transpose((step(X,12) |X) ,12) ) ,7) ) ,-5) ) ,12) ) ,12) ) ,7) ) ) ) +transpose(shuffle(((shuffle(step(X,12) ) +((shuffle(transpose(transpose(X,-7) ,-5) ) +transpose((((echo(X,4,6) +transpose(shuffle(X) ,12) ) +transpose((((transpose(X,4) |step(X,12) ) +transpose(((X+transpose(transpose(X,-5) ,4) ) +transpose(echo(X,4,6) ,7) ) ,4) ) +transpose(shuffle(X) ,7) ) ,4) ) +transpose((((X+transpose(X,12) ) +transpose((transpose(X,4) |X) ,4) ) +transpose((X|((X+transpose(X,4) ) +transpose(X,7) ) ) ,7) ) ,7) ) ,4) ) +transpose(((shuffle(transpose(X,4) ) +transpose(step((X+arpeggio(X) ) ,12) ,4) ) +transpose(((X+transpose(X,4) ) +transpose(transpose(echo(X,4,6) ,-7) ,7) ) ,7) ) ,7) ) ) +transpose(transpose(step(transpose((shuffle(((X+X) |echo(X,4,6) ) ) +transpose(transpose(transpose(X,4) ,4) ,7) ) ,-7) ,12) ,-7) ,7) ) ) ,4) ) |((arpeggio((transpose((((transpose(arpeggio(echo(echo(X,4,6) ,4,6) ) ,-5) |step(step((transpose(X,-5) +transpose(echo(X,4,6) ,7) ) ,12) ,12) ) +transpose(shuffle(arpeggio(((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(((shuffle(X) +transpose((X|X) ,4) ) +transpose(X,7) ) ,4) ) +transpose(transpose(transpose(X,4) ,-5) ,7) ) ) ) ,4) ) +transpose(shuffle(arpeggio((echo(arpeggio(X) ,4,6) |(X+transpose((step(X,12) +transpose(arpeggio(X) ,12) ) ,12) ) ) ) ) ,7) ) ,-7) +transpose((echo((echo((echo(((X+transpose(X,4) ) +transpose(X,7) ) ,4,6) +transpose(((X+transpose(X,7) ) |X) ,12) ) ,4,6) +transpose(transpose(((shuffle((X+transpose(X,7) ) ) +transpose(shuffle(X) ,4) ) +transpose(transpose(X,-5) ,7) ) ,4) ,12) ) ,4,6) +arpeggio(transpose(arpeggio(transpose((X+transpose(shuffle(X) ,7) ) ,4) ) ,4) ) ) ,4) ) ) +transpose(transpose(step(((((transpose(shuffle(X) ,4) |shuffle(step(step(((arpeggio(X) +transpose((X+transpose(X,7) ) ,4) ) +transpose((X+transpose(X,7) ) ,7) ) ,12) ,12) ) ) +transpose(shuffle(step(((X+transpose(X,4) ) +transpose(shuffle(X) ,7) ) ,12) ) ,4) ) +transpose(transpose(step(transpose((X+transpose(echo((X+transpose(X,12) ) ,4,6) ,7) ) ,-7) ,12) ,4) ,7) ) |echo(step(transpose(transpose(transpose(X,4) ,-5) ,-7) ,12) ,4,6) ) ,12) ,-5) ,4) ) +transpose((transpose((echo(step(transpose(transpose(X,4) ,4) ,12) ,4,6) |transpose((shuffle(transpose(transpose(X,-5) ,-5) ) +transpose(step(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-5) ,12) ,7) ) ,4) ) ,-5) +arpeggio(transpose(shuffle(shuffle(echo(echo(shuffle(X) ,4,6) ,4,6) ) ) ,-7) ) ) ,7) ) )
random seed used was 218647075

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