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((((step(shuffle(transpose((arpeggio(transpose(((shuffle(X) +transpose((X+transpose(X,7) ) ,12) ) +echo(transpose(X,-7) ,4,6) ) ,-7) ) +transpose(arpeggio((transpose(X,4) +X) ) ,12) ) ,4) ) ,12) +transpose(transpose(transpose((transpose(transpose((((X+transpose(X,12) ) +transpose(X,12) ) +transpose(shuffle(X) ,7) ) ,-5) ,4) |(((X+transpose(X,7) ) +transpose(transpose(X,4) ,4) ) +transpose(X,7) ) ) ,4) ,-7) ,12) ) +transpose((arpeggio(echo(transpose(shuffle(transpose(shuffle((X+X) ) ,-5) ) ,-5) ,4,6) ) +transpose(echo(transpose(step(arpeggio((((transpose(arpeggio(shuffle(X) ) ,-5) +transpose(arpeggio(((X+transpose(X,4) ) +transpose(X,7) ) ) ,4) ) +transpose(transpose(((X+transpose(X,12) ) +transpose(X,12) ) ,-7) ,7) ) |transpose(((shuffle(X) +transpose(X,12) ) +arpeggio(X) ) ,4) ) ) ,12) ,-5) ,4,6) ,12) ) ,-5) ) +shuffle(transpose((transpose(((((transpose(transpose((arpeggio(((X+transpose(X,4) ) +transpose(X,7) ) ) +transpose(transpose(X,4) ,12) ) ,-7) ,-7) |transpose(step((echo(transpose(X,4) ,4,6) +transpose(arpeggio(X) ,12) ) ,12) ,-7) ) +transpose(transpose(transpose(arpeggio(step(transpose(X,-5) ,12) ) ,4) ,-5) ,12) ) +transpose(transpose(((((arpeggio(transpose((shuffle(X) +transpose(X,12) ) ,4) ) +transpose(shuffle(transpose(X,-5) ) ,4) ) +transpose((transpose(shuffle(X) ,4) +shuffle(X) ) ,7) ) +echo(((arpeggio(X) +transpose(arpeggio(X) ,4) ) +transpose(transpose(arpeggio(X) ,4) ,7) ) ,4,6) ) |(transpose(transpose(transpose((shuffle(transpose((X|X) ,-7) ) +shuffle(X) ) ,-5) ,4) ,-5) +shuffle(((shuffle(shuffle(arpeggio(X) ) ) +transpose((shuffle(transpose(((shuffle(X) +transpose(X,4) ) +transpose(echo(X,4,6) ,7) ) ,4) ) +transpose(arpeggio(step((transpose(X,-5) +transpose(X,7) ) ,12) ) ,7) ) ,7) ) +transpose((step((shuffle(transpose(X,-5) ) +transpose(transpose(X,-5) ,7) ) ,12) +transpose(transpose(((shuffle(X) |arpeggio(X) ) |(X+transpose(X,-5) ) ) ,4) ,-5) ) ,7) ) ) ) ) ,4) ,4) ) +transpose(((arpeggio(transpose((transpose((X+(X|X) ) ,-5) +transpose((shuffle(((X+transpose(X,4) ) +transpose(X,7) ) ) |(((X+X) |X) +transpose(X,4) ) ) ,12) ) ,4) ) +transpose(transpose(transpose((X+transpose(shuffle((X+transpose(X,7) ) ) ,7) ) ,-5) ,-7) ,4) ) +transpose((echo(((step((transpose(X,-5) +transpose((X+(X+X) ) ,12) ) ,12) +transpose(arpeggio(X) ,4) ) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) ,4,6) +transpose(echo(((arpeggio(arpeggio(shuffle(X) ) ) +transpose(echo(X,4,6) ,4) ) +transpose((transpose((X+X) ,-5) +transpose(transpose(X,-5) ,7) ) ,7) ) ,4,6) ,12) ) ,7) ) ,7) ) ,-7) +transpose(step(transpose((transpose(step(transpose(arpeggio(X) ,4) ,12) ,4) +transpose(((transpose(((step(X,12) |((X+transpose(X,12) ) +transpose((X|X) ,12) ) ) +transpose(arpeggio(arpeggio(X) ) ,7) ) ,-7) |((shuffle((X+arpeggio(X) ) ) +transpose(transpose(step(X,12) ,-7) ,12) ) +echo((X+transpose(X,7) ) ,4,6) ) ) +step((((X|(X+X) ) +transpose((X+X) ,4) ) +transpose(arpeggio((X|X) ) ,7) ) ,12) ) ,12) ) ,-7) ,12) ,4) ) ,4) ) ) ,-7) +transpose(step(shuffle(((step(((echo(step(shuffle((X+arpeggio(transpose(step(X,12) ,-7) ) ) ) ,12) ,4,6) |arpeggio(step(shuffle(arpeggio((((X+transpose(shuffle(X) ,7) ) +(((X+transpose(X,7) ) +transpose(transpose(X,-5) ,12) ) |transpose(shuffle(X) ,4) ) ) +arpeggio((((X+X) +transpose(arpeggio(X) ,7) ) |transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-5) ) ) ) ) ) ,12) ) ) +transpose(transpose(transpose(echo(shuffle(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-7) ) ,4,6) ,4) ,-7) ,4) ) ,12) +transpose(arpeggio(step((arpeggio(arpeggio((arpeggio((step(transpose(((X+transpose(X,7) ) +transpose(transpose(X,-7) ,12) ) ,4) ,12) +transpose(transpose(arpeggio(X) ,-5) ,7) ) ) +arpeggio(shuffle(arpeggio(step(((X+transpose(transpose(X,4) ,4) ) +transpose(X,7) ) ,12) ) ) ) ) ) ) +transpose(step(transpose(arpeggio(transpose(transpose(echo(((X+X) +transpose(arpeggio(X) ,7) ) ,4,6) ,-7) ,-7) ) ,-5) ,12) ,12) ) ,12) ) ,12) ) +transpose((transpose(transpose(((((transpose(echo(arpeggio(X) ,4,6) ,-7) +transpose(transpose(echo(shuffle(transpose(X,-7) ) ,4,6) ,4) ,7) ) +transpose(arpeggio(((arpeggio(transpose(arpeggio(arpeggio(arpeggio(transpose(X,4) ) ) ) ,-5) ) +transpose(arpeggio(((step(X,12) +transpose((step(X,12) +(X+transpose(X,7) ) ) ,4) ) +transpose(step(X,12) ,7) ) ) ,4) ) +transpose(transpose(((((X+X) |echo(X,4,6) ) +transpose(X,4) ) +transpose((X+transpose(X,7) ) ,7) ) ,-5) ,7) ) ) ,7) ) +transpose(shuffle(transpose((((transpose(X,-5) +echo(X,4,6) ) |transpose(X,4) ) +(shuffle(X) +((X+transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) ) +transpose(X,7) ) ) ) ,-7) ) ,4) ) +transpose(arpeggio(((transpose(transpose(shuffle(shuffle(X) ) ,-7) ,-7) +transpose(step(((arpeggio(step(X,12) ) +shuffle(X) ) |arpeggio((transpose(step(X,12) ,-5) |transpose(transpose(X,4) ,-5) ) ) ) ,12) ,4) ) +transpose(transpose(shuffle(shuffle((transpose((X|X) ,4) +transpose(step(transpose(echo(X,4,6) ,-7) ,12) ,7) ) ) ) ,-5) ,7) ) ) ,7) ) ,-5) ,-5) +transpose(shuffle(echo(((shuffle(((transpose(arpeggio((X+transpose(arpeggio(X) ,7) ) ) ,-7) +transpose(((((shuffle(X) +transpose(X,-5) ) +transpose(((X+X) +transpose((X+transpose(X,12) ) ,7) ) ,12) ) +transpose(shuffle((arpeggio((X+transpose(X,-5) ) ) +transpose(shuffle(shuffle(X) ) ,7) ) ) ,7) ) +(step((X|shuffle(X) ) ,12) +(shuffle(X) +(step(arpeggio(X) ,12) +transpose(transpose(transpose(X,-5) ,-7) ,7) ) ) ) ) ,7) ) |((((shuffle(transpose(arpeggio((X+transpose(X,7) ) ) ,-5) ) +transpose(((transpose(X,-7) +transpose(transpose(X,4) ,12) ) |echo(X,4,6) ) ,7) ) +transpose(((step(X,12) +transpose(X,12) ) |step(transpose(X,-5) ,12) ) ,4) ) +transpose(transpose(arpeggio((((echo(X,4,6) +transpose(transpose(X,-7) ,7) ) +transpose(transpose(transpose(transpose(X,-5) ,-7) ,-7) ,4) ) +transpose((arpeggio(transpose((X+X) ,-5) ) +shuffle(transpose(X,-7) ) ) ,7) ) ) ,-7) ,7) ) |shuffle(transpose((((((transpose(step(X,12) ,4) +transpose(shuffle(X) ,4) ) +transpose((X+transpose(X,7) ) ,7) ) +transpose((X+transpose(X,7) ) ,4) ) +transpose(transpose(arpeggio(shuffle(X) ) ,-5) ,4) ) +transpose(((X+transpose(X,4) ) +transpose(arpeggio(X) ,12) ) ,7) ) ,4) ) ) ) ) +transpose(arpeggio(arpeggio(transpose(shuffle(arpeggio(X) ) ,4) ) ) ,7) ) |(step(transpose(step(transpose((shuffle(arpeggio(transpose(transpose(X,4) ,-5) ) ) +transpose(((X+transpose(transpose(X,4) ,7) ) +transpose((X+X) ,-7) ) ,12) ) ,-7) ,12) ,4) ,12) +(echo(shuffle(echo(arpeggio(transpose(arpeggio(X) ,-7) ) ,4,6) ) ,4,6) |transpose(shuffle((shuffle(((X|X) +transpose(transpose(X,4) ,7) ) ) +transpose(transpose(echo(transpose(X,-5) ,4,6) ,-7) ,7) ) ) ,-7) ) ) ) ,4,6) ) ,7) ) ,12) ) ) ,12) ,4) ) +transpose(shuffle(transpose(transpose(transpose(shuffle(((transpose(((shuffle(echo(((echo(X,4,6) +(X+transpose(X,12) ) ) +transpose(step(X,12) ,12) ) ,4,6) ) +transpose((arpeggio(shuffle(transpose(X,-5) ) ) |transpose(step(X,12) ,-7) ) ,7) ) |(transpose((((transpose(transpose(X,-7) ,-5) +transpose((shuffle(X) +transpose((X+transpose(X,7) ) ,7) ) ,4) ) +transpose(transpose(arpeggio(X) ,4) ,7) ) +((step(transpose(X,-7) ,12) +transpose(((X|X) +(X+X) ) ,4) ) +transpose(arpeggio(echo(X,4,6) ) ,7) ) ) ,4) +transpose(step(transpose((X+shuffle(X) ) ,4) ,12) ,4) ) ) ,4) |(transpose((((transpose((((X+X) |shuffle(X) ) +transpose(transpose((X+X) ,-5) ,4) ) ,-7) +transpose(step((transpose(echo(((transpose(transpose(X,-7) ,-7) +transpose(X,4) ) +transpose(transpose((X+transpose(X,12) ) ,-5) ,7) ) ,4,6) ,4) +transpose(transpose((X|(X|X) ) ,-5) ,12) ) ,12) ,4) ) +transpose((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(arpeggio(arpeggio(X) ) ,12) ) ,7) ) +transpose((arpeggio(((transpose(transpose(X,4) ,-5) |transpose((X+X) ,-5) ) |arpeggio((step(X,12) +transpose((((X+transpose(X,4) ) +transpose(X,7) ) +X) ,7) ) ) ) ) +((transpose(transpose((X|transpose(X,4) ) ,4) ,-7) +transpose(shuffle(transpose(shuffle(transpose(transpose((X|X) ,4) ,-5) ) ,-5) ) ,4) ) +transpose(((arpeggio(shuffle(X) ) +(transpose(X,-5) |transpose(X,4) ) ) |transpose(X,-5) ) ,7) ) ) ,7) ) ,-5) |(transpose(transpose((arpeggio(echo(shuffle(arpeggio(((shuffle(echo(X,4,6) ) +transpose(X,4) ) +transpose((X+X) ,7) ) ) ) ,4,6) ) |((((X+X) |transpose(shuffle((X|X) ) ,4) ) +transpose((echo(transpose(X,-7) ,4,6) +transpose(transpose(X,-7) ,-7) ) ,12) ) |transpose(((arpeggio(shuffle(X) ) +transpose(transpose(X,4) ,7) ) +transpose((echo((X|X) ,4,6) +transpose(transpose(X,-7) ,7) ) ,12) ) ,4) ) ) ,-5) ,-7) |(((arpeggio(shuffle(transpose(arpeggio((X+transpose(X,7) ) ) ,-7) ) ) +transpose(transpose(transpose(X,-5) ,-7) ,4) ) +transpose(echo(((X|transpose(X,-7) ) +transpose(X,12) ) ,4,6) ,7) ) +echo(arpeggio(step((echo(arpeggio(X) ,4,6) |transpose(X,-5) ) ,12) ) ,4,6) ) ) ) ) +transpose(((shuffle(transpose(arpeggio(transpose(X,4) ) ,-7) ) +transpose(shuffle(shuffle(transpose(echo((transpose(X,4) +transpose(arpeggio(X) ,7) ) ,4,6) ,-7) ) ) ,4) ) +transpose((arpeggio((shuffle(shuffle(shuffle((echo(X,4,6) +transpose(arpeggio(X) ,12) ) ) ) ) |shuffle(shuffle(transpose((echo((X+transpose(arpeggio(X) ,12) ) ,4,6) |transpose(arpeggio((X+transpose(X,7) ) ) ,-7) ) ,-7) ) ) ) ) +shuffle((shuffle((step(echo(arpeggio(transpose(X,-7) ) ,4,6) ,12) |(transpose(((transpose(X,4) +transpose(shuffle(X) ,4) ) +transpose(step(X,12) ,7) ) ,4) +transpose(arpeggio((echo(X,4,6) |transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-5) ) ) ,12) ) ) ) +arpeggio(arpeggio(((((X|(X+transpose(X,7) ) ) +transpose(arpeggio(transpose(X,-5) ) ,4) ) +transpose(shuffle(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) ) ,7) ) +transpose(transpose(((X+X) |shuffle(X) ) ,-5) ,7) ) ) ) ) ) ) ,7) ) ,7) ) ) ,-5) ,4) ,-7) ) ,7) )
random seed used was 3691115

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