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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# of Tracks:
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After 20 generations the expression "X" became this:
transpose(((step(((step(((shuffle(step((transpose((((transpose(X,-5) +((X+transpose(X,4) ) +transpose(X,7) ) ) +transpose(transpose(((transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-5) +transpose((X+transpose(X,12) ) ,4) ) +transpose(arpeggio(X) ,7) ) ,-7) ,4) ) +transpose(transpose(X,-5) ,7) ) ,4) +transpose(step(echo(shuffle(((transpose(arpeggio(X) ,-5) +transpose(arpeggio(step(X,12) ) ,4) ) +transpose(((X+transpose(transpose((X+X) ,-5) ,4) ) +transpose(((X+transpose(X,12) ) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) ,7) ) ,7) ) ) ,4,6) ,12) ,7) ) ,12) ) +transpose(transpose(transpose(transpose(((echo(X,4,6) +transpose((X+transpose(X,7) ) ,7) ) +transpose(X,12) ) ,4) ,-5) ,-5) ,12) ) +transpose(transpose((transpose(transpose(((transpose(X,-7) +transpose(X,7) ) +transpose(shuffle(X) ,-5) ) ,-7) ,-7) +transpose((transpose(transpose((transpose(step(X,12) ,-5) |transpose(transpose(X,4) ,4) ) ,-7) ,-7) +transpose(echo(((arpeggio(X) +transpose((X+transpose(X,7) ) ,12) ) +transpose((X+X) ,12) ) ,4,6) ,7) ) ,12) ) ,4) ,12) ) ,12) +transpose((transpose(transpose(step(transpose((((transpose(X,-7) +transpose((X+transpose(X,12) ) ,12) ) +transpose(step(shuffle(transpose(step(echo(X,4,6) ,12) ,-5) ) ,12) ,4) ) +transpose(transpose(transpose(X,-7) ,-5) ,7) ) ,-7) ,12) ,-5) ,4) +transpose(((echo(transpose(echo(transpose(((X+transpose(X,7) ) +transpose(transpose(transpose((X+X) ,4) ,-7) ,12) ) ,-7) ,4,6) ,-7) ,4,6) +transpose(echo(((((step(((X+transpose((X+transpose(X,12) ) ,4) ) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) ,12) +transpose(transpose(transpose(arpeggio(X) ,-7) ,-7) ,4) ) +transpose((((X+transpose(X,7) ) +transpose(echo(X,4,6) ,12) ) +transpose(arpeggio(transpose(X,-5) ) ,12) ) ,7) ) +transpose(transpose((echo(X,4,6) +transpose(step(X,12) ,12) ) ,4) ,7) ) +transpose((transpose(echo(X,4,6) ,-7) +transpose((transpose(X,-5) |X) ,12) ) ,12) ) ,4,6) ,4) ) +transpose((((((((X+transpose(X,7) ) +shuffle(arpeggio(X) ) ) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-7) ) +transpose((((X+transpose(X,12) ) +transpose(shuffle(X) ,4) ) +transpose(echo(X,4,6) ,7) ) ,-7) ) +transpose((((step((X+transpose(X,7) ) ,12) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) +transpose(transpose(shuffle(transpose(shuffle(X) ,-7) ) ,4) ,4) ) +transpose(echo((transpose(X,-7) +transpose(X,12) ) ,4,6) ,7) ) ,4) ) +transpose(step(transpose(transpose(step(echo(arpeggio(X) ,4,6) ,12) ,-5) ,-5) ,12) ,7) ) +transpose((transpose(transpose(transpose(shuffle(arpeggio(echo(X,4,6) ) ) ,-7) ,-5) ,-7) +shuffle(transpose(echo(X,4,6) ,-7) ) ) ,12) ) ,7) ) ,7) ) ,12) ) |(((echo(transpose(echo((step(step(X,12) ,12) +transpose(arpeggio(transpose((X+transpose(X,12) ) ,-5) ) ,7) ) ,4,6) ,-5) ,4,6) +transpose(transpose(shuffle((((X+transpose(X,7) ) +transpose(transpose(X,4) ,7) ) +transpose((step(transpose(X,-7) ,12) +transpose(transpose(step(X,12) ,-7) ,12) ) ,12) ) ) ,-7) ,7) ) |arpeggio(transpose((shuffle(arpeggio(transpose((X+X) ,-7) ) ) |(((echo(X,4,6) +transpose(echo(X,4,6) ,4) ) +transpose((transpose(X,-5) +transpose(transpose(transpose(X,-7) ,-5) ,12) ) ,7) ) +transpose(((X+transpose(X,7) ) +transpose(transpose(X,-7) ,7) ) ,12) ) ) ,-5) ) ) +(transpose(((echo(((shuffle((X+X) ) +transpose(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-7) ,4) ) +transpose((step(X,12) +transpose(X,-5) ) ,7) ) ,4,6) +transpose((echo(((step(transpose(X,-7) ,12) +transpose(((echo(step(X,12) ,4,6) +transpose(transpose(step(transpose(X,-5) ,12) ,-7) ,4) ) +transpose(echo(X,4,6) ,7) ) ,7) ) +transpose(arpeggio(X) ,-5) ) ,4,6) +transpose((shuffle(echo(X,4,6) ) +transpose((transpose(transpose(X,-7) ,-5) +transpose(transpose(transpose((X+transpose(shuffle(X) ,12) ) ,4) ,4) ,12) ) ,7) ) ,12) ) ,4) ) +transpose((transpose(transpose((((transpose(((X+transpose(X,7) ) +transpose(echo(X,4,6) ,12) ) ,-7) +transpose(transpose(transpose((X+transpose(X,7) ) ,-5) ,-7) ,12) ) +transpose(((X|(X+transpose(X,12) ) ) +transpose(X,4) ) ,4) ) +transpose(shuffle(transpose(X,-7) ) ,7) ) ,-7) ,-5) +transpose(((((transpose(transpose(X,-7) ,-5) +transpose(echo(X,4,6) ,7) ) +transpose(shuffle(transpose(step(X,12) ,-7) ) ,7) ) +transpose((transpose(echo(arpeggio(echo(X,4,6) ) ,4,6) ,-5) +transpose(arpeggio((transpose(X,-7) +transpose(echo(X,4,6) ,12) ) ) ,7) ) ,4) ) +transpose(echo(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-7) ,4,6) ,7) ) ,7) ) ,7) ) ,-5) +transpose(step((transpose(echo(transpose(transpose((X|X) ,-5) ,-7) ,4,6) ,4) +transpose(transpose(transpose(step(shuffle(((transpose((transpose(X,-7) |transpose(X,-7) ) ,-5) +transpose(transpose(X,4) ,4) ) +transpose(transpose(echo(X,4,6) ,4) ,7) ) ) ,12) ,-5) ,4) ,7) ) ,12) ,12) ) ) ) ,12) |echo((step((transpose(echo(shuffle(arpeggio(X) ) ,4,6) ,-7) |shuffle(echo((X+X) ,4,6) ) ) ,12) +transpose(step(transpose(transpose(transpose((transpose(((((X+transpose(transpose(X,-7) ,12) ) +transpose(step(X,12) ,4) ) +transpose(((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(X,4) ) +transpose(transpose(X,-5) ,7) ) ,7) ) |(transpose(X,4) +transpose(shuffle(X) ,12) ) ) ,-5) +transpose(arpeggio(((transpose(X,-5) +transpose(echo(X,4,6) ,12) ) +(echo(echo(X,4,6) ,4,6) +transpose((shuffle(transpose(X,-5) ) +transpose(transpose((X+transpose(echo(X,4,6) ,12) ) ,-5) ,7) ) ,12) ) ) ) ,7) ) ,-5) ,-5) ,-5) ,12) ,7) ) ,4,6) ) +transpose(((transpose(((transpose(step(shuffle(((transpose(transpose(echo((X+transpose(X,7) ) ,4,6) ,-5) ,-5) +transpose(((((step(X,12) +transpose(transpose(X,-5) ,12) ) |echo(((X+transpose(X,4) ) +transpose(X,7) ) ,4,6) ) |(X+transpose(X,12) ) ) +transpose(((X+transpose(step(X,12) ,4) ) +transpose(arpeggio(X) ,7) ) ,7) ) ,12) ) +transpose(transpose((((step((transpose(X,-7) +transpose(echo(X,4,6) ,12) ) ,12) +transpose(shuffle(transpose(((transpose(X,-5) +transpose(X,4) ) +transpose(arpeggio(X) ,7) ) ,-5) ) ,4) ) +transpose((((((X+transpose(transpose(X,-7) ,4) ) +transpose(arpeggio(X) ,7) ) +transpose(transpose(transpose(X,-5) ,4) ,4) ) +transpose((X+transpose(X,12) ) ,7) ) +transpose(transpose(transpose(X,-7) ,-5) ,7) ) ,7) ) |step(transpose(transpose(X,-7) ,-5) ,12) ) ,4) ,7) ) ) ,12) ,-7) |echo((transpose((((((((X+X) +transpose(X,7) ) +transpose(transpose(step(X,12) ,-5) ,4) ) +transpose(shuffle((X+transpose(transpose(X,4) ,12) ) ) ,7) ) +transpose(shuffle(transpose(transpose(X,-7) ,-7) ) ,4) ) +transpose(transpose(((X+transpose(arpeggio(X) ,4) ) +transpose(X,7) ) ,-7) ,7) ) +transpose((arpeggio((transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-7) +transpose(X,12) ) ) +(((echo(X,4,6) |X) +transpose(transpose(transpose((X+transpose(transpose(X,-7) ,7) ) ,-5) ,-5) ,12) ) +transpose(transpose(shuffle((transpose(transpose(X,-5) ,-7) +transpose(shuffle(transpose(X,-7) ) ,12) ) ) ,4) ,7) ) ) ,12) ) ,-5) +arpeggio(transpose((((transpose(transpose(echo(step(transpose(transpose(X,-7) ,-5) ,12) ,4,6) ,-5) ,-5) +transpose(transpose(transpose((((transpose(X,4) +transpose(transpose(X,4) ,12) ) +transpose(transpose(X,-5) ,12) ) |((transpose(transpose(X,-5) ,-5) |((X+transpose(X,4) ) +transpose(X,7) ) ) +transpose((step(X,12) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) ,12) ) ) ,-7) ,-5) ,4) ) +transpose(((transpose(((arpeggio(X) +transpose(X,12) ) |(X|X) ) ,-7) +transpose(transpose(((X+shuffle(transpose(X,-7) ) ) +transpose(arpeggio((X+transpose(X,12) ) ) ,7) ) ,-5) ,4) ) +transpose((((echo(transpose(((X|X) +transpose(X,-7) ) ,4) ,4,6) +transpose(step(transpose(X,-7) ,12) ,12) ) +transpose(step((arpeggio(X) +transpose(transpose(X,-7) ,12) ) ,12) ,7) ) |(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-5) +transpose((X+transpose(X,12) ) ,12) ) ) ,7) ) ,7) ) +transpose(((shuffle(transpose(echo(X,4,6) ,-7) ) +transpose(((((X+X) +transpose(echo((transpose(X,4) +transpose((X|X) ,12) ) ,4,6) ,4) ) +transpose(transpose(echo(X,4,6) ,4) ,7) ) +transpose(transpose(shuffle(transpose(X,-5) ) ,-7) ,7) ) ,12) ) +((((((((transpose(X,-7) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,12) ) +transpose(arpeggio(X) ,12) ) +transpose((transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-5) +transpose(transpose(X,-7) ,7) ) ,12) ) +transpose(transpose(((shuffle(echo(X,4,6) ) +transpose(echo(X,4,6) ,4) ) +transpose((((X+X) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) ) +transpose((X|X) ,7) ) ,7) ) ,4) ,4) ) +transpose(transpose(shuffle(transpose(transpose(X,-5) ,-5) ) ,-7) ,7) ) +transpose((transpose(shuffle(transpose(X,-7) ) ,-7) +transpose(step(((step(arpeggio(X) ,12) +transpose(((X+transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) ) +transpose((X+transpose(X,12) ) ,7) ) ,4) ) +transpose(step(X,12) ,7) ) ,12) ,7) ) ,7) ) |(shuffle(transpose(transpose((X+transpose(X,12) ) ,4) ,-7) ) +(((transpose((X+transpose(X,7) ) ,-5) +transpose(transpose((X+transpose(X,12) ) ,-5) ,12) ) +transpose(((transpose(transpose(X,4) ,-5) +transpose(transpose(X,-5) ,4) ) +transpose(transpose(X,-7) ,7) ) ,4) ) +transpose((transpose(X,-5) +transpose(transpose(shuffle(X) ,-7) ,7) ) ,7) ) ) ) +transpose(transpose((transpose(step(transpose(transpose(shuffle(X) ,-7) ,-7) ,12) ,-5) +transpose(step(step(echo((X+transpose(X,7) ) ,4,6) ,12) ,12) ,12) ) ,-7) ,12) ) ) ,7) ) ,-7) ) ) ,4,6) ) +transpose(transpose(step(((X+transpose(((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(echo(X,4,6) ,4) ) +transpose(shuffle(X) ,7) ) ,4) ) +transpose((X+transpose(X,7) ) ,7) ) ,12) ,-5) ,4) ) ,-5) +transpose(echo(shuffle((step((transpose((transpose(transpose((((X+transpose(X,12) ) |X) |((X|X) +transpose((X+transpose(X,12) ) ,7) ) ) ,-7) ,4) +transpose((((transpose(((step(X,12) +transpose(echo(X,4,6) ,4) ) +transpose(transpose(X,-5) ,7) ) ,-5) +transpose((transpose((arpeggio(X) +transpose(transpose(X,-7) ,12) ) ,-7) +transpose(transpose(X,-7) ,7) ) ,12) ) +(X+transpose(step(X,12) ,7) ) ) +transpose(((((step((X+transpose(X,12) ) ,12) +transpose(arpeggio(X) ,7) ) +transpose((X+transpose(echo(X,4,6) ,7) ) ,7) ) +transpose(transpose(transpose(((X+transpose(X,7) ) +transpose(transpose(X,-5) ,12) ) ,-5) ,-5) ,12) ) +((arpeggio((X+transpose(X,7) ) ) +transpose(transpose(step(echo(X,4,6) ,12) ,-7) ,7) ) +transpose(((X|X) +transpose((X|X) ,7) ) ,7) ) ) ,7) ) ,7) ) ,-5) +transpose(shuffle(transpose((transpose(transpose(transpose(transpose(X,-5) ,-7) ,-5) ,-7) +transpose(((arpeggio((X+transpose(arpeggio(X) ,12) ) ) +transpose(echo(echo(echo(X,4,6) ,4,6) ,4,6) ,12) ) +transpose(arpeggio(transpose(echo(transpose(X,-5) ,4,6) ,-7) ) ,12) ) ,12) ) ,4) ) ,12) ) ,12) +(((transpose(((transpose((((transpose(echo(X,4,6) ,-7) +transpose((transpose((transpose(X,4) +transpose((X+transpose(X,12) ) ,7) ) ,-7) +transpose((X+transpose(transpose((X+transpose(X,12) ) ,4) ,12) ) ,7) ) ,4) ) +transpose(transpose(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-7) ,-5) ,7) ) +transpose((X+transpose(X,7) ) ,7) ) ,-5) +transpose(transpose(transpose(((X+transpose((X+transpose(X,12) ) ,4) ) +transpose(X,7) ) ,-5) ,-5) ,12) ) +transpose((step(((transpose(echo(X,4,6) ,-5) +transpose(shuffle(((transpose((X+X) ,4) +transpose(transpose(transpose(X,-7) ,-7) ,4) ) +transpose((step(X,12) +transpose((X+transpose(X,12) ) ,12) ) ,7) ) ) ,12) ) +transpose(arpeggio((((X+transpose(X,7) ) +transpose((transpose(X,-5) +transpose(X,12) ) ,4) ) +transpose(((step(X,12) +transpose(X,4) ) +transpose(echo(X,4,6) ,7) ) ,7) ) ) ,12) ) ,12) +transpose(transpose((transpose((transpose(X,4) |X) ,-7) |transpose(transpose(X,-7) ,-7) ) ,4) ,7) ) ,7) ) ,-7) +transpose(step(transpose((transpose(((X+transpose(X,7) ) +transpose(shuffle(X) ,7) ) ,4) +transpose(arpeggio(((echo(arpeggio(X) ,4,6) +transpose((((X+transpose(transpose(X,-7) ,4) ) +transpose(echo(X,4,6) ,7) ) +transpose(shuffle(X) ,12) ) ,4) ) +transpose(X,7) ) ) ,4) ) ,-7) ,12) ,-5) ) +transpose((transpose((step((shuffle(arpeggio(X) ) |echo(transpose((((transpose(X,-5) +transpose(transpose(X,-7) ,4) ) +transpose(((X+transpose((X+transpose(X,7) ) ,4) ) +transpose(X,7) ) ,7) ) +transpose(shuffle(((X+transpose(X,12) ) +transpose(X,12) ) ) ,7) ) ,-5) ,4,6) ) ,12) |((arpeggio(shuffle((X|X) ) ) +transpose(shuffle(transpose(echo(X,4,6) ,-7) ) ,7) ) +transpose(shuffle(step(arpeggio(((transpose(transpose(transpose(X,-5) ,-5) ,-7) +transpose(shuffle(((X+transpose(X,4) ) +transpose(X,7) ) ) ,4) ) +transpose(step(arpeggio(X) ,12) ,7) ) ) ,12) ) ,7) ) ) ,-7) +transpose(shuffle(step(transpose((transpose(transpose(X,-5) ,-7) +transpose(arpeggio(transpose((((transpose(X,-7) +transpose(X,4) ) +transpose((X+X) ,7) ) +((X+transpose(X,7) ) +X) ) ,-5) ) ,7) ) ,-7) ,12) ) ,7) ) ,4) ) +transpose(transpose(((transpose(echo(transpose(shuffle(transpose((X+X) ,-7) ) ,-7) ,4,6) ,-5) +transpose(((transpose(((X+transpose(X,12) ) |X) ,-5) +(arpeggio(((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(shuffle((X+transpose(X,7) ) ) ,4) ) +transpose((X+transpose(X,-7) ) ,7) ) ) +transpose(transpose(X,4) ,7) ) ) |(transpose(transpose(X,-7) ,-5) +transpose((transpose(shuffle(X) ,-5) +transpose(((X+transpose(transpose(X,-7) ,4) ) +transpose(X,7) ) ,12) ) ,7) ) ) ,4) ) +transpose(shuffle(((shuffle((transpose(step((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(shuffle(X) ,12) ) ,12) ,-7) +transpose((step(X,12) +transpose(shuffle(((X+transpose(X,4) ) +transpose(X,7) ) ) ,12) ) ,12) ) ) +transpose(((((((X+transpose((X+transpose(X,-5) ) ,4) ) +transpose(step(X,12) ,7) ) +transpose(transpose(X,-7) ,7) ) +transpose(shuffle(shuffle(X) ) ,12) ) +transpose(((transpose(X,-7) +(X+transpose(transpose(transpose(X,-5) ,-7) ,7) ) ) |echo(((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(X,7) ) +transpose((X+transpose((X|X) ,12) ) ,12) ) ,4,6) ) ,4) ) +transpose((shuffle(transpose(transpose(X,-5) ,-7) ) +(step(transpose(X,4) ,12) +transpose((shuffle(X) +transpose(transpose(X,-5) ,7) ) ,7) ) ) ,7) ) ,4) ) +transpose((transpose((transpose(X,-7) +transpose((transpose(X,-5) +transpose(X,12) ) ,12) ) ,-7) +transpose(((((step(X,12) +transpose(shuffle(X) ,4) ) +transpose(transpose(X,4) ,7) ) +transpose(X,12) ) +transpose(step(arpeggio(transpose((X|X) ,-7) ) ,12) ,12) ) ,12) ) ,7) ) ) ,7) ) ,-7) ,7) ) ) ) ,4,6) ,4) ) +transpose(transpose((echo(((((((step(arpeggio(X) ,12) +transpose((arpeggio(transpose(X,-5) ) +transpose((X+shuffle(arpeggio(X) ) ) ,12) ) ,7) ) |(arpeggio(echo(transpose(X,4) ,4,6) ) +echo(X,4,6) ) ) +transpose(echo(arpeggio((((transpose(echo(X,4,6) ,-5) +transpose((X+transpose((X|X) ,12) ) ,7) ) +transpose(((X+transpose(X,12) ) +(X|X) ) ,4) ) +transpose(transpose((echo(X,4,6) +(X+transpose(X,7) ) ) ,-5) ,7) ) ) ,4,6) ,7) ) +transpose((step(arpeggio(((transpose(transpose(X,-5) ,-7) +transpose((((shuffle(X) +transpose(X,4) ) +transpose(transpose(X,-7) ,7) ) +transpose((shuffle(X) |X) ,7) ) ,4) ) +transpose(transpose(shuffle(X) ,-5) ,7) ) ) ,12) +transpose(transpose(echo((echo((transpose((X|X) ,-7) +transpose(step(step(X,12) ,12) ,7) ) ,4,6) |transpose(transpose((X+transpose(X,7) ) ,-5) ,4) ) ,4,6) ,-5) ,7) ) ,4) ) +transpose(((transpose(transpose(transpose(X,-5) ,-7) ,4) +transpose(transpose(X,-7) ,12) ) +transpose(echo((X+transpose(X,7) ) ,4,6) ,7) ) ,7) ) +transpose(((arpeggio(transpose(echo((X|X) ,4,6) ,-5) ) +transpose(((transpose(transpose((X|(transpose(X,-5) +transpose(transpose(X,4) ,12) ) ) ,-7) ,-5) +transpose((shuffle((transpose(transpose(X,-5) ,-5) +step(echo(echo(X,4,6) ,4,6) ,12) ) ) +echo((X+transpose((X+transpose(X,12) ) ,12) ) ,4,6) ) ,4) ) +transpose(echo(transpose(X,-7) ,4,6) ,7) ) ,4) ) +transpose(arpeggio(transpose(transpose((echo(X,4,6) +transpose(transpose(X,-7) ,7) ) ,-7) ,-5) ) ,7) ) ,12) ) ,4,6) +transpose(step(transpose(shuffle(transpose((transpose(echo(X,4,6) ,-7) +shuffle(transpose(X,-5) ) ) ,-5) ) ,-5) ,12) ,12) ) ,-7) ,7) ) ,7) ) ,-7)
random seed used was 73222987

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