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:
(((shuffle(shuffle((transpose(transpose((arpeggio(((X+transpose(X,7) ) |(transpose(echo(X,4,6) ,4) |step(X,12) ) ) ) +(echo(transpose((echo(X,4,6) |(X+transpose(X,12) ) ) ,-5) ,4,6) +transpose((arpeggio(transpose(X,-5) ) +(X+transpose(transpose(X,-5) ,12) ) ) ,12) ) ) ,-7) ,4) |(step(transpose(shuffle(transpose(step(transpose((transpose(X,4) +transpose(((X+transpose(X,12) ) +transpose((X+transpose(X,7) ) ,12) ) ,12) ) ,4) ,12) ,4) ) ,-7) ,12) +transpose(arpeggio((step(transpose(transpose(((transpose(X,-5) |X) |arpeggio(X) ) ,-5) ,-7) ,12) +step(transpose(X,-7) ,12) ) ) ,-7) ) ) ) ) |(shuffle(((transpose(transpose((((step(shuffle(((X|X) +transpose(transpose(X,-5) ,12) ) ) ,12) +transpose(transpose(((X+X) +transpose(X,7) ) ,-5) ,4) ) +transpose(echo(transpose(shuffle(X) ,-7) ,4,6) ,7) ) |(echo(transpose(arpeggio((arpeggio(shuffle(X) ) |arpeggio(X) ) ) ,-5) ,4,6) |((transpose(transpose(X,-5) ,-5) +transpose((X+transpose(X,12) ) ,7) ) |(X+X) ) ) ) ,-7) ,4) +transpose((transpose(echo((echo((X+X) ,4,6) +transpose(transpose(transpose((((transpose(X,-5) +transpose(echo(X,4,6) ,4) ) +transpose(transpose(X,4) ,7) ) +transpose(transpose(transpose(X,4) ,4) ,7) ) ,-5) ,4) ,7) ) ,4,6) ,4) |(echo(transpose((echo(transpose(X,-7) ,4,6) +transpose((transpose(arpeggio(X) ,-5) +(arpeggio((X|X) ) |((X|X) +transpose(X,7) ) ) ) ,7) ) ,4) ,4,6) |transpose((transpose(transpose((arpeggio(step(transpose(X,-5) ,12) ) +transpose((X|X) ,12) ) ,4) ,4) +(transpose(((X|X) +transpose(arpeggio(transpose(X,-7) ) ,12) ) ,-7) +arpeggio(shuffle(X) ) ) ) ,4) ) ) ,12) ) |transpose(step(step(transpose(transpose(transpose(arpeggio(X) ,-5) ,4) ,-5) ,12) ,12) ,-5) ) ) |(((transpose(transpose(transpose(shuffle((transpose(transpose((X+transpose(X,12) ) ,-5) ,-5) |(X|X) ) ) ,-7) ,4) ,-7) |(((((shuffle(transpose(step(X,12) ,4) ) +echo(X,4,6) ) +transpose(transpose((X|X) ,-5) ,12) ) |(transpose((step(transpose(X,4) ,12) +transpose((echo(transpose(X,-7) ,4,6) +transpose(X,4) ) ,7) ) ,4) +transpose(echo(((X|X) +(X|X) ) ,4,6) ,7) ) ) +transpose(transpose((transpose(transpose(X,4) ,-7) +transpose(((X+transpose(X,7) ) +transpose((X+transpose(X,12) ) ,7) ) ,7) ) ,-7) ,4) ) +transpose((shuffle(transpose(transpose(X,4) ,-7) ) +transpose(shuffle(X) ,12) ) ,7) ) ) +transpose(((echo(transpose(arpeggio((shuffle((X+transpose(X,12) ) ) +transpose((echo((X|X) ,4,6) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,12) ) ,12) ) ) ,-7) ,4,6) +transpose(((((step(shuffle(((X|X) |transpose(X,4) ) ) ,12) +transpose(echo(transpose(transpose(transpose(X,4) ,-7) ,-7) ,4,6) ,7) ) +(transpose(shuffle(transpose((X|transpose(X,-5) ) ,4) ) ,-7) +transpose(transpose(((step(step(X,12) ,12) +transpose(transpose(transpose(shuffle(X) ,4) ,4) ,4) ) +transpose(transpose((shuffle(transpose(X,-7) ) +transpose((X+transpose(X,7) ) ,12) ) ,-5) ,7) ) ,-5) ,7) ) ) |((((((X+X) +transpose(arpeggio(X) ,12) ) +transpose(arpeggio(transpose(X,-7) ) ,12) ) |((transpose(X,-5) |X) +transpose(transpose(X,-7) ,12) ) ) +transpose(transpose(shuffle(X) ,-7) ,4) ) +transpose(transpose(((X|X) +transpose((X|X) ,12) ) ,-5) ,7) ) ) +(echo((transpose((X|X) ,-5) |step((((transpose(X,-7) +transpose(shuffle(X) ,4) ) +transpose(X,7) ) +transpose(transpose(X,-5) ,12) ) ,12) ) ,4,6) |transpose(transpose(transpose((X+transpose(echo(X,4,6) ,12) ) ,4) ,-7) ,4) ) ) ,7) ) |(transpose(((((transpose(X,-7) +(transpose(X,-5) +(X|X) ) ) +transpose(arpeggio(transpose(X,-7) ) ,12) ) +transpose((transpose(step(X,12) ,-5) +transpose(step(X,12) ,7) ) ,4) ) +transpose(transpose((shuffle(X) +transpose(transpose(X,-5) ,7) ) ,-7) ,7) ) ,4) |transpose(transpose(((arpeggio(transpose(transpose(X,-7) ,-7) ) |transpose(transpose((((X+transpose(X,7) ) +transpose(step(echo(X,4,6) ,12) ,4) ) +transpose(transpose(X,-7) ,7) ) ,-7) ,-5) ) +transpose(arpeggio(transpose(shuffle(X) ,-5) ) ,12) ) ,-5) ,-5) ) ) ,12) ) |(transpose(transpose((shuffle((((transpose(step((X+(X+transpose(X,12) ) ) ,12) ,4) +shuffle(transpose(X,-5) ) ) |transpose((transpose(step(shuffle(step(X,12) ) ,12) ,-7) |echo(X,4,6) ) ,-5) ) +transpose((transpose(echo(shuffle(shuffle(X) ) ,4,6) ,4) +transpose(((X+step(X,12) ) |((shuffle(transpose(X,-5) ) +transpose(echo(X,4,6) ,4) ) +transpose(((X+transpose(X,7) ) +transpose(((X+transpose((X|X) ,4) ) +transpose(X,7) ) ,12) ) ,7) ) ) ,12) ) ,12) ) ) +(transpose(echo(transpose(echo((X+transpose(transpose(X,4) ,12) ) ,4,6) ,4) ,4,6) ,-5) |arpeggio((echo(((X+transpose(X,12) ) +X) ,4,6) +transpose((X|shuffle((X+transpose(X,12) ) ) ) ,7) ) ) ) ) ,4) ,-7) +arpeggio((transpose(transpose(transpose(echo(X,4,6) ,-5) ,-7) ,4) +transpose(transpose((((((transpose((X|X) ,-7) +transpose(transpose(transpose(transpose(X,4) ,4) ,-7) ,12) ) +transpose(step(arpeggio(transpose((X|(X|X) ) ,-5) ) ,12) ,4) ) +transpose(echo((transpose((transpose(X,4) +transpose(transpose(X,-7) ,7) ) ,-7) +transpose(transpose(arpeggio(transpose(X,4) ) ,-5) ,12) ) ,4,6) ,7) ) +transpose(echo(arpeggio((((shuffle((X+X) ) +transpose(transpose((X+transpose(X,12) ) ,4) ,4) ) +transpose(arpeggio(step(X,12) ) ,7) ) +transpose(transpose(arpeggio(X) ,4) ,12) ) ) ,4,6) ,4) ) +transpose(transpose(step((transpose(transpose(shuffle(X) ,-7) ,-5) +transpose(transpose(X,4) ,7) ) ,12) ,-7) ,7) ) ,4) ,12) ) ) ) ) ) ) +transpose(transpose((step(step(transpose(((transpose(transpose((((arpeggio(transpose((((X+transpose(X,12) ) +transpose(X,7) ) |transpose((X|X) ,-7) ) ,-7) ) |arpeggio(transpose(X,4) ) ) +arpeggio(arpeggio((((X+transpose(X,7) ) +transpose(arpeggio(transpose(transpose(X,-7) ,4) ) ,4) ) +transpose(transpose(((X+transpose((X+transpose(X,12) ) ,4) ) +transpose(transpose(X,4) ,7) ) ,4) ,7) ) ) ) ) +transpose((transpose(transpose(X,-5) ,-7) |((shuffle(transpose(X,-7) ) +step(echo(transpose(X,-5) ,4,6) ,12) ) +transpose(arpeggio(transpose(X,-7) ) ,7) ) ) ,7) ) ,-5) ,-5) +transpose(transpose(transpose(transpose(transpose(((shuffle(X) +transpose(transpose(X,4) ,7) ) +transpose(transpose((X|X) ,4) ,7) ) ,-5) ,-7) ,-7) ,4) ,12) ) +transpose(transpose((transpose(((echo(shuffle(X) ,4,6) +transpose((step(X,12) +transpose(transpose((X+transpose(X,12) ) ,-5) ,12) ) ,7) ) |echo(shuffle((X+transpose(X,12) ) ) ,4,6) ) ,4) +transpose(transpose((((X|X) +transpose(transpose(X,-7) ,4) ) +transpose(arpeggio(transpose(transpose(X,-7) ,-5) ) ,7) ) ,4) ,7) ) ,-7) ,7) ) ,-5) ,12) ,12) +((((transpose(step(arpeggio((transpose(transpose(arpeggio(transpose(X,-7) ) ,4) ,4) |(arpeggio(echo((((X+transpose(X,12) ) +transpose(transpose(X,-5) ,4) ) +transpose(transpose(X,-5) ,7) ) ,4,6) ) |(((X+transpose((X|transpose(X,-5) ) ,4) ) +transpose(((transpose(X,-7) |echo(X,4,6) ) +transpose((step(X,12) +transpose(shuffle(X) ,12) ) ,12) ) ,7) ) |(transpose(X,-7) +transpose(transpose(arpeggio(X) ,-5) ,7) ) ) ) ) ) ,12) ,-5) +transpose(shuffle((step(transpose((shuffle(arpeggio(transpose(X,-7) ) ) +(transpose(transpose(X,4) ,4) |transpose(echo(transpose(X,4) ,4,6) ,-7) ) ) ,-5) ,12) +(transpose(transpose(step(((((transpose(transpose(X,-7) ,-7) +transpose(transpose((X+transpose((X+transpose(X,7) ) ,12) ) ,-5) ,12) ) +transpose((X+transpose(X,7) ) ,12) ) +transpose((transpose(transpose(X,-5) ,4) |(transpose((X|X) ,-5) +transpose(step(transpose(X,4) ,12) ,7) ) ) ,4) ) +transpose(transpose((X+transpose(X,12) ) ,4) ,7) ) ,12) ,-5) ,-5) +transpose((((((shuffle(X) +transpose(transpose(transpose(X,-5) ,-7) ,4) ) +transpose(((transpose(X,-7) +transpose((X+transpose(X,12) ) ,4) ) +transpose(echo(X,4,6) ,7) ) ,7) ) +transpose((transpose((X+transpose(X,7) ) ,-7) +shuffle(shuffle((X+transpose(X,12) ) ) ) ) ,4) ) +transpose((echo(step(transpose(X,4) ,12) ,4,6) +transpose(((transpose(((X|X) +transpose((X+transpose(X,7) ) ,12) ) ,4) +transpose(echo((X|transpose(X,4) ) ,4,6) ,4) ) +transpose(((X+transpose(X,12) ) +transpose(transpose(X,-7) ,7) ) ,7) ) ,7) ) ,7) ) +transpose(transpose(step((X|echo(X,4,6) ) ,12) ,4) ,7) ) ,-7) ) ) ) ,4) ) +transpose(((((((step(X,12) +(step(X,12) |step(X,12) ) ) +echo(transpose((((((X+transpose(X,4) ) +transpose(X,7) ) |(((X+transpose(X,12) ) |shuffle(X) ) +transpose(arpeggio(X) ,7) ) ) +transpose(echo((X+X) ,4,6) ,4) ) +transpose(arpeggio(echo((X|shuffle(X) ) ,4,6) ) ,7) ) ,-5) ,4,6) ) +transpose(step(shuffle((transpose(shuffle(X) ,4) +transpose(echo((transpose(X,-5) +transpose(X,12) ) ,4,6) ,12) ) ) ,12) ,4) ) +transpose((arpeggio((transpose(((transpose((X|X) ,4) +transpose(transpose(X,-7) ,7) ) |echo(transpose(X,-7) ,4,6) ) ,-5) |echo(((X+transpose(transpose(X,4) ,12) ) +transpose(X,7) ) ,4,6) ) ) |(((((X|transpose(X,-5) ) |((X|X) +transpose((X+X) ,12) ) ) |transpose(transpose(transpose(X,-5) ,4) ,-5) ) +transpose((transpose(X,-7) +transpose(shuffle(X) ,12) ) ,7) ) +transpose(((transpose(((step(transpose(X,-5) ,12) +transpose((transpose(transpose(X,4) ,-5) +transpose(X,12) ) ,4) ) +transpose(step(((X+transpose(X,4) ) +transpose(X,7) ) ,12) ,7) ) ,4) +transpose((((transpose((X+transpose(X,-5) ) ,-7) |(arpeggio(X) +transpose((transpose(X,-5) +transpose(transpose(X,-7) ,7) ) ,12) ) ) +transpose((X+transpose(X,12) ) ,4) ) +transpose((arpeggio(transpose(X,-7) ) |transpose(((X|X) |(X|X) ) ,-7) ) ,7) ) ,4) ) +transpose((transpose(((X|X) +transpose(transpose(X,4) ,7) ) ,-5) +transpose(shuffle(step(transpose(transpose(X,-5) ,-7) ,12) ) ,7) ) ,7) ) ,7) ) ) ,7) ) +transpose(transpose((transpose(shuffle(echo((transpose(X,-5) |(X+transpose(X,12) ) ) ,4,6) ) ,4) +transpose((shuffle((((X+transpose(transpose(X,-5) ,7) ) |((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(transpose(X,4) ,4) ) +transpose(X,7) ) ) |transpose(transpose(X,4) ,-7) ) ) +transpose(transpose((echo(transpose((X+transpose(X,12) ) ,-7) ,4,6) |(transpose((X|X) ,-5) +transpose(X,4) ) ) ,-5) ,12) ) ,7) ) ,-7) ,-5) ) +transpose(transpose((transpose(transpose(transpose((step((X+transpose(X,12) ) ,12) +transpose(((transpose(X,-7) +transpose(echo(X,4,6) ,12) ) +transpose(((step(X,12) +transpose(shuffle(X) ,4) ) +transpose(arpeggio(X) ,7) ) ,12) ) ,7) ) ,-5) ,-7) ,4) |(echo(transpose((transpose(X,-5) +transpose(((X|X) |transpose(X,-5) ) ,7) ) ,4) ,4,6) +transpose((echo((transpose((shuffle(transpose(X,4) ) +echo(X,4,6) ) ,-7) +transpose(transpose(X,-7) ,12) ) ,4,6) +transpose(echo(step(((X+transpose(transpose(X,4) ,12) ) +transpose(shuffle(transpose(X,-5) ) ,7) ) ,12) ,4,6) ,12) ) ,12) ) ) ,-5) ,12) ) ,7) ) +transpose(shuffle(step(((transpose(((transpose(((X+transpose(step(X,12) ,12) ) |echo(shuffle(X) ,4,6) ) ,4) +transpose(transpose((X|((X+transpose(X,4) ) +transpose(X,7) ) ) ,4) ,12) ) +transpose(((transpose(X,-7) |((X+transpose(X,4) ) +transpose(X,7) ) ) +transpose(shuffle((X+X) ) ,12) ) ,7) ) ,-7) +transpose((transpose((transpose(echo(X,4,6) ,-7) +transpose(transpose(arpeggio(X) ,-7) ,12) ) ,-7) +((X+transpose((X+transpose(X,7) ) ,12) ) +((X+transpose((X|X) ,7) ) |echo(transpose(X,-7) ,4,6) ) ) ) ,7) ) +(echo(((transpose((X+transpose(X,12) ) ,-7) |(X+transpose(X,12) ) ) |arpeggio(arpeggio(transpose(X,4) ) ) ) ,4,6) +transpose(transpose(echo(step(X,12) ,4,6) ,-5) ,12) ) ) ,12) ) ,12) ) +transpose((transpose(transpose(shuffle(arpeggio((transpose(transpose((arpeggio(X) +transpose((X+transpose(X,12) ) ,12) ) ,-5) ,-5) |transpose(arpeggio((X+X) ) ,-5) ) ) ) ,-7) ,4) +transpose((transpose(step(step(X,12) ,12) ,-5) +transpose(transpose((transpose(transpose(X,4) ,-5) +transpose((X|shuffle(((X+transpose(transpose(X,-7) ,4) ) +transpose(transpose(X,-7) ,7) ) ) ) ,7) ) ,-7) ,7) ) ,7) ) ,-7) ) ) ,-5) ,12) ) +transpose((step(transpose(shuffle(transpose(echo((transpose(arpeggio(((transpose((X+transpose(X,7) ) ,-7) |(transpose(X,-5) +transpose(echo(X,4,6) ,7) ) ) +transpose((transpose(((X+transpose(X,7) ) |(X+transpose(X,12) ) ) ,-5) +transpose((X+transpose(X,7) ) ,7) ) ,7) ) ) ,4) |step(transpose((X+transpose(X,7) ) ,4) ,12) ) ,4,6) ,-7) ) ,-7) ,12) +((((shuffle(transpose(transpose(X,-5) ,4) ) +transpose(((transpose((X+X) ,-7) +transpose(((X+transpose(((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(shuffle(X) ,4) ) +transpose(X,7) ) ,7) ) |(X+(X+X) ) ) ,4) ) +transpose(((step(X,12) +transpose(shuffle(X) ,4) ) +transpose(X,7) ) ,7) ) ,7) ) +transpose(echo(((((transpose((transpose(X,4) +transpose(echo(X,4,6) ,7) ) ,4) +transpose(((transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) +(X|X) ) |(X|transpose(arpeggio(X) ,4) ) ) ,4) ) +transpose(step(((transpose(X,-7) +transpose(X,7) ) |step((X+transpose(X,7) ) ,12) ) ,12) ,7) ) +transpose(transpose(echo((arpeggio((X+transpose(X,12) ) ) +transpose(echo(X,4,6) ,12) ) ,4,6) ,4) ,4) ) +transpose(shuffle((echo((X|X) ,4,6) +transpose(transpose(((((X+transpose(X,4) ) +transpose(X,7) ) +transpose((X+transpose(X,7) ) ,4) ) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) ,4) ,7) ) ) ,7) ) ,4,6) ,12) ) |transpose(transpose((transpose((transpose(X,-5) +echo(X,4,6) ) ,-5) +transpose((((X+transpose(X,7) ) +transpose(transpose((transpose(X,-7) |(X+X) ) ,4) ,12) ) +transpose(transpose(transpose((X+transpose(X,12) ) ,4) ,-5) ,7) ) ,7) ) ,-7) ,-5) ) +transpose((transpose(transpose(transpose(transpose(step(transpose(transpose(X,4) ,-5) ,12) ,-5) ,-5) ,4) ,4) +transpose(step(((((transpose((echo(X,4,6) +transpose((echo((X+transpose(X,12) ) ,4,6) +transpose((echo(X,4,6) |step(X,12) ) ,12) ) ,12) ) ,-7) |transpose((X+X) ,-7) ) +transpose(transpose(transpose((((((X+X) |(X|X) ) +transpose(transpose(transpose(X,-5) ,4) ,4) ) +transpose(((X+transpose((X+X) ,4) ) +transpose(X,7) ) ,7) ) +transpose(transpose(echo(transpose((X+transpose((X+transpose(X,12) ) ,7) ) ,-5) ,4,6) ,-7) ,7) ) ,-5) ,-7) ,4) ) +transpose(((transpose(((X|X) +transpose(X,7) ) ,4) +transpose((transpose(echo(step(X,12) ,4,6) ,-5) +transpose(echo(X,4,6) ,7) ) ,12) ) +transpose(echo(transpose(X,4) ,4,6) ,12) ) ,7) ) +arpeggio(transpose(transpose(transpose(echo(transpose(arpeggio(X) ,-5) ,4,6) ,-5) ,4) ,-7) ) ) ,12) ,7) ) ,12) ) ) ,4) )
random seed used was 113160512

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