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:
echo(((((arpeggio((transpose(transpose(transpose(transpose(transpose(echo(transpose(((transpose(X,4) +transpose(X,4) ) +transpose(X,7) ) ,-7) ,4,6) ,-5) ,-7) ,-5) ,-5) ,-5) +shuffle((transpose((transpose((transpose(shuffle(echo(X,4,6) ) ,-5) +((X+transpose(X,12) ) +transpose(shuffle(transpose(X,4) ) ,-7) ) ) ,4) +transpose(shuffle(((transpose(shuffle(X) ,-5) +transpose(((X+transpose(X,7) ) +X) ,4) ) +transpose((transpose(X,-7) +X) ,7) ) ) ,12) ) ,-5) +transpose(shuffle(transpose(transpose((transpose(transpose(X,-7) ,-5) |(echo(X,4,6) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,12) ) ) ,-7) ,-5) ) ,4) ) ) ) ) +transpose(transpose(transpose((step(echo(arpeggio((transpose(X,4) +transpose(transpose((X|X) ,-5) ,4) ) ) ,4,6) ,12) +((transpose(((transpose(((X+transpose(X,-5) ) +transpose(X,12) ) ,4) +transpose(transpose(X,-7) ,12) ) +(echo(X,4,6) +echo(X,4,6) ) ) ,-7) +transpose(transpose((arpeggio(shuffle((((X|X) +transpose(X,-5) ) +transpose((transpose(X,-7) +transpose(X,7) ) ,7) ) ) ) +transpose(((transpose(X,-5) +transpose(((X+transpose(X,12) ) +(X|X) ) ,4) ) +transpose((((X+transpose(X,4) ) +transpose(X,7) ) +transpose((X|X) ,7) ) ,7) ) ,7) ) ,4) ,4) ) +transpose(((transpose(transpose((((X|X) +X) |(X+transpose(X,7) ) ) ,-5) ,-7) +transpose(arpeggio(shuffle(transpose(X,-5) ) ) ,12) ) |(((arpeggio((X|X) ) +transpose(X,-7) ) +transpose(((X+((X+transpose(X,4) ) +transpose(X,7) ) ) |transpose(X,-7) ) ,12) ) +step(X,12) ) ) ,7) ) ) ,-7) ,-7) ,7) ) +transpose(step(((transpose(echo(arpeggio((((echo(echo((transpose((X+transpose(X,7) ) ,4) +((X+transpose(X,7) ) +(X|X) ) ) ,4,6) ,4,6) +transpose((arpeggio(arpeggio(X) ) +transpose(transpose(step(arpeggio(X) ,12) ,-5) ,7) ) ,4) ) +transpose(transpose(((((echo(X,4,6) +transpose((X|X) ,4) ) +transpose(X,7) ) +echo(step(X,12) ,4,6) ) +X) ,-5) ,7) ) |echo(transpose((((transpose(shuffle(X) ,-5) +transpose(transpose(X,4) ,12) ) +transpose(step((X+transpose(X,12) ) ,12) ,4) ) +transpose((transpose(transpose(X,-7) ,-7) +transpose(((transpose(X,4) +transpose(transpose((X|X) ,4) ,4) ) +transpose((X+transpose(X,-5) ) ,7) ) ,12) ) ,7) ) ,-7) ,4,6) ) ) ,4,6) ,-5) +shuffle(step((((arpeggio(transpose((transpose(step(((X|X) |X) ,12) ,4) +transpose((step(X,12) +transpose((X+step(X,12) ) ,12) ) ,7) ) ,4) ) +transpose((transpose(transpose((((X+X) +transpose((transpose(X,-5) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) ,12) ) +transpose(((((X+transpose(X,4) ) +transpose(X,7) ) +transpose((X+X) ,12) ) +transpose(arpeggio((X+transpose(X,7) ) ) ,12) ) ,7) ) ,-7) ,-7) +(transpose(transpose(transpose(shuffle(transpose(echo(X,4,6) ,-7) ) ,-7) ,-5) ,-5) +transpose(echo(echo(shuffle(X) ,4,6) ,4,6) ,7) ) ) ,12) ) +transpose((((transpose((((X+transpose(X,12) ) +transpose(X,4) ) +transpose(transpose(X,-7) ,7) ) ,-7) +transpose(step(transpose(X,-5) ,12) ,12) ) |(transpose(transpose(X,4) ,-5) +(((X+transpose(X,4) ) +transpose(X,7) ) +shuffle((X+transpose(X,7) ) ) ) ) ) +arpeggio(transpose(transpose((transpose(X,-7) +echo((X|X) ,4,6) ) ,4) ,-5) ) ) ,4) ) +arpeggio(arpeggio(echo((transpose(arpeggio(arpeggio((X+transpose(X,7) ) ) ) ,4) |((X+X) +transpose((X+X) ,12) ) ) ,4,6) ) ) ) ,12) ) ) +((transpose((shuffle(((arpeggio((X+transpose(step(X,12) ,12) ) ) +transpose((X|X) ,7) ) +step(transpose(X,-7) ,12) ) ) |(step(transpose(echo(step(transpose(X,-7) ,12) ,4,6) ,-5) ,12) +transpose(transpose(arpeggio(transpose((X+(transpose(transpose(X,-7) ,-5) +echo(transpose(X,4) ,4,6) ) ) ,-5) ) ,-7) ,12) ) ) ,-5) +transpose(transpose(shuffle(transpose((arpeggio((arpeggio(echo(arpeggio((X+X) ) ,4,6) ) +transpose(shuffle(transpose(step(X,12) ,-5) ) ,12) ) ) +transpose((transpose(arpeggio((X+X) ) ,4) +transpose((transpose(((((transpose(X,-5) +transpose(transpose(X,4) ,4) ) +transpose(transpose(X,-7) ,7) ) +transpose(step(((X+transpose(X,4) ) +transpose((X+X) ,7) ) ,12) ,4) ) +transpose(transpose(X,-7) ,7) ) ,-7) +transpose(arpeggio(((X+transpose(X,12) ) |((X+X) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) ) ) ,12) ) ,12) ) ,4) ) ,4) ) ,-7) ,4) ) +transpose(transpose(((shuffle(echo(step(echo(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-5) ,4,6) ,12) ,4,6) ) |step((transpose(((arpeggio((X+transpose(X,7) ) ) +transpose(arpeggio(transpose(X,4) ) ,4) ) +transpose((transpose(X,4) +transpose((transpose(X,4) +transpose(X,12) ) ,12) ) ,7) ) ,-5) |(echo(((X+transpose(shuffle(X) ,12) ) |transpose((X+transpose(X,7) ) ,-5) ) ,4,6) +step(X,12) ) ) ,12) ) +((transpose((((X+transpose(X,12) ) +transpose(X,4) ) +transpose(echo(X,4,6) ,7) ) ,-5) +transpose(transpose(transpose(step(X,12) ,-5) ,4) ,7) ) +transpose(transpose(shuffle(transpose(transpose(echo((X|X) ,4,6) ,-7) ,-5) ) ,4) ,7) ) ) ,4) ,7) ) ) ,12) ,4) ) +transpose(((((((transpose(((transpose((X+X) ,4) +transpose((((X+X) +transpose((X+X) ,-7) ) +step((X+transpose(X,7) ) ,12) ) ,7) ) +(arpeggio(arpeggio((step(X,12) |(X+transpose(X,7) ) ) ) ) +transpose(transpose((transpose(X,-5) |transpose(X,-7) ) ,-5) ,12) ) ) ,-7) +transpose((((transpose((echo(arpeggio(transpose(X,-7) ) ,4,6) +transpose(((shuffle(X) +transpose(X,12) ) +transpose(transpose((X+transpose(X,7) ) ,4) ,7) ) ,7) ) ,4) +transpose((transpose(((transpose(X,-7) +transpose((((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(X,4) ) +transpose((X+X) ,7) ) +transpose((X|arpeggio(X) ) ,12) ) ,4) ) +transpose(step(((X|X) |echo(X,4,6) ) ,12) ,7) ) ,-7) +((transpose(X,-7) +(transpose(X,-5) +shuffle(X) ) ) +transpose(echo(transpose(transpose(transpose(X,-5) ,-5) ,-5) ,4,6) ,12) ) ) ,4) ) +transpose(((transpose((shuffle((shuffle(X) +transpose(transpose(X,4) ,12) ) ) +(transpose(X,-5) +(X+transpose(X,7) ) ) ) ,-5) +transpose((transpose(transpose((X+transpose((X+X) ,7) ) ,4) ,-7) +(transpose((((arpeggio(transpose(X,-7) ) +transpose(X,7) ) +transpose(arpeggio((X|(X|X) ) ) ,4) ) +transpose(echo((X|X) ,4,6) ,7) ) ,4) |((transpose(transpose((X+X) ,-7) ,-7) +transpose(((X+transpose(X,12) ) +((X+transpose(transpose(X,-5) ,4) ) +transpose(shuffle(X) ,7) ) ) ,4) ) +transpose((shuffle(step(transpose(X,4) ,12) ) +transpose(transpose(X,-7) ,12) ) ,7) ) ) ) ,4) ) +transpose(step(transpose(((((X+X) +X) +transpose(transpose(transpose(X,-7) ,-5) ,4) ) +transpose(echo(((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(X,4) ) +transpose(shuffle(X) ,7) ) ,4,6) ,7) ) ,4) ,12) ,7) ) ,7) ) +transpose((transpose(echo((X|(X+transpose(X,12) ) ) ,4,6) ,-7) +((transpose(transpose(transpose(transpose(X,-7) ,-7) ,4) ,-7) |((X+transpose((transpose(X,-7) |((X+transpose(X,4) ) +transpose(X,7) ) ) ,4) ) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) ) |(arpeggio(((arpeggio(X) +transpose((X+X) ,12) ) +(X+transpose(X,12) ) ) ) +transpose(transpose(transpose(shuffle(X) ,-5) ,-5) ,12) ) ) ) ,4) ) ,12) ) +transpose(echo(echo(arpeggio(echo((((step(X,12) |transpose(X,-5) ) +transpose((X+X) ,4) ) |X) ,4,6) ) ,4,6) ,4,6) ,4) ) +transpose((transpose(((transpose((((X+X) +transpose(((X+transpose(X,4) ) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) ,7) ) +transpose(X,7) ) ,-5) |transpose(((((((X+transpose(X,4) ) +transpose(X,7) ) |X) +((X|X) +X) ) +(transpose(X,-5) |transpose(transpose(X,-7) ,-5) ) ) +transpose(transpose(transpose(step(X,12) ,-7) ,-5) ,12) ) ,-5) ) |(shuffle(transpose(((transpose(X,-7) +transpose(X,7) ) |echo(X,4,6) ) ,4) ) +transpose((((shuffle(transpose(X,-7) ) +transpose((transpose(step((X+X) ,12) ,-5) |transpose(echo((X|X) ,4,6) ,4) ) ,4) ) +transpose(transpose((X+(transpose(X,-7) +(X+transpose(X,12) ) ) ) ,-5) ,7) ) +transpose((step((((X|X) +X) +transpose(X,12) ) ,12) +(X+transpose(X,7) ) ) ,7) ) ,-5) ) ) ,-7) +((transpose(transpose(transpose(echo((transpose((X+transpose(X,12) ) ,4) +(shuffle(X) +transpose((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(X,7) ) ,7) ) ) ,4,6) ,-7) ,4) ,4) +transpose(transpose(arpeggio(transpose(transpose((transpose(transpose(X,4) ,4) +transpose(arpeggio((step(X,12) +transpose(shuffle(X) ,12) ) ) ,12) ) ,-7) ,4) ) ,-7) ,12) ) +(arpeggio((transpose(step(X,12) ,4) +transpose((((X+transpose(X,7) ) |(X|X) ) +transpose((transpose(X,-5) |X) ,12) ) ,4) ) ) |transpose(((transpose(X,4) +shuffle((X+X) ) ) +transpose(((X+transpose(step(X,12) ,7) ) |(X|echo(X,4,6) ) ) ,7) ) ,-7) ) ) ) ,7) ) +transpose(step(shuffle(arpeggio(echo(transpose(echo((transpose((X|((X+transpose(X,4) ) +transpose(X,7) ) ) ,-7) +transpose(transpose(X,-7) ,12) ) ,4,6) ,4) ,4,6) ) ) ,12) ,4) ) +transpose(transpose((transpose(shuffle(shuffle((step((X+transpose(X,12) ) ,12) +transpose(transpose(((X+X) |X) ,-7) ,7) ) ) ) ,4) +transpose(((((X|X) +transpose(X,4) ) +(step(((X+transpose(X,4) ) +transpose(X,7) ) ,12) +(echo(X,4,6) |transpose(X,-5) ) ) ) |(((((arpeggio(X) +transpose(X,4) ) +transpose(X,7) ) |((X+X) +transpose((X+transpose(X,7) ) ,7) ) ) +transpose(((X|(X+X) ) |(X+X) ) ,12) ) +transpose(step(shuffle((X+transpose(X,12) ) ) ,12) ,12) ) ) ,12) ) ,-7) ,7) ) +transpose(step(step(step(arpeggio(((X+transpose(transpose(X,4) ,12) ) +transpose((transpose((arpeggio(X) +transpose((echo(X,4,6) |X) ,4) ) ,-5) +transpose((shuffle(((X+X) +X) ) +((((X|X) +transpose(transpose(X,4) ,4) ) +transpose(X,7) ) +transpose(step((X|X) ,12) ,12) ) ) ,7) ) ,7) ) ) ,12) ,12) ,12) ,-7) ) ,7) ) +transpose((transpose((shuffle((shuffle((step(((((X+transpose(transpose(X,-5) ,4) ) +transpose((transpose(X,4) +transpose((X+X) ,12) ) ,7) ) +transpose((X+transpose((X+((X+transpose(X,4) ) +transpose(X,7) ) ) ,12) ) ,4) ) +transpose(transpose(X,-7) ,7) ) ,12) |((X|X) +transpose((transpose(transpose(echo(X,4,6) ,-7) ,-5) +transpose((X+transpose(X,4) ) ,-5) ) ,7) ) ) ) |transpose(step(((transpose(echo(X,4,6) ,-7) +transpose(X,4) ) +transpose(arpeggio(arpeggio(transpose(X,-5) ) ) ,7) ) ,12) ,-5) ) ) +(transpose(transpose((echo(transpose(echo((((transpose(X,-5) |(X+transpose(X,7) ) ) +transpose((echo(X,4,6) +(X+X) ) ,4) ) +transpose(shuffle(X) ,7) ) ,4,6) ,-7) ,4,6) +transpose((step(echo((transpose(transpose(((X|X) +X) ,-7) ,-5) +shuffle(transpose(transpose(transpose(X,-7) ,-5) ,-5) ) ) ,4,6) ,12) +transpose(arpeggio(step(((X|X) |step(X,12) ) ,12) ) ,-5) ) ,7) ) ,-7) ,-7) +step(transpose((((arpeggio(arpeggio(((X|X) +transpose(echo(((X+transpose(X,4) ) +transpose(X,7) ) ,4,6) ,7) ) ) ) |((echo(transpose((X+((X|X) +((X+transpose(X,4) ) +transpose(X,7) ) ) ) ,4) ,4,6) +transpose((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(((X+transpose(X,-7) ) +transpose(X,4) ) ,7) ) ,4) ) +transpose(step((X|(X+transpose(X,12) ) ) ,12) ,7) ) ) +transpose(((transpose(transpose(((X|X) +transpose(X,4) ) ,4) ,4) +((shuffle(X) +transpose(transpose((X+X) ,4) ,7) ) +transpose(transpose(X,-7) ,4) ) ) +transpose(transpose(transpose(arpeggio((X+X) ) ,-5) ,4) ,7) ) ,4) ) +transpose((((transpose(transpose((X|(X+transpose(X,7) ) ) ,-5) ,4) +transpose(step(((step(X,12) +transpose(shuffle(X) ,4) ) +transpose((X+X) ,7) ) ,12) ,7) ) +transpose(shuffle(transpose((transpose(transpose(X,-5) ,4) +transpose(transpose(X,4) ,4) ) ,4) ) ,4) ) +transpose((((step((X+X) ,12) +transpose(X,12) ) |transpose(X,4) ) +transpose(X,-7) ) ,7) ) ,7) ) ,4) ,12) ) ) ,4) +transpose((transpose(((((transpose((echo((arpeggio(X) +transpose(transpose(X,-7) ,7) ) ,4,6) +transpose(transpose((step(X,12) +transpose(X,12) ) ,-5) ,12) ) ,-5) |echo(transpose((X|arpeggio(transpose((X+transpose(X,7) ) ,-5) ) ) ,-5) ,4,6) ) +transpose(transpose(arpeggio(transpose(((transpose(shuffle(X) ,4) |((((X+X) +transpose(X,4) ) +transpose(transpose(X,-5) ,7) ) +((X|X) +transpose(X,-7) ) ) ) +transpose(transpose(X,-5) ,4) ) ,4) ) ,-7) ,4) ) +transpose(transpose(((((transpose((X+transpose(transpose(X,-5) ,7) ) ,4) +transpose(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) ,4) ) +transpose(transpose(echo(transpose((X+X) ,-5) ,4,6) ,4) ,7) ) +transpose(((transpose(X,4) +transpose(echo(echo(X,4,6) ,4,6) ,12) ) |transpose(((transpose((X+transpose(X,12) ) ,4) +transpose(transpose(X,-5) ,12) ) |(transpose(X,-5) +(X|X) ) ) ,-5) ) ,7) ) +((X+(X|X) ) |(echo((transpose((X|X) ,4) +(((X+X) +transpose(X,4) ) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) ) ,4,6) |step(shuffle(arpeggio((X+transpose(X,7) ) ) ) ,12) ) ) ) ,-5) ,7) ) +transpose(((step((transpose(((((X+X) +transpose((transpose(X,-5) +transpose((X+transpose(X,7) ) ,12) ) ,7) ) +transpose(shuffle(echo(transpose((X+transpose(X,7) ) ,4) ,4,6) ) ,4) ) +transpose(transpose((((X+transpose(X,4) ) +transpose(X,7) ) +(X+transpose(X,12) ) ) ,4) ,7) ) ,-7) +transpose(step(transpose(step(transpose(transpose(((X+transpose(X,7) ) |(X|X) ) ,4) ,4) ,12) ,4) ,12) ,12) ) ,12) +transpose((shuffle(echo(transpose((step(X,12) |(X|X) ) ,-7) ,4,6) ) |(echo(transpose(echo(X,4,6) ,-5) ,4,6) +shuffle(transpose(echo(((X+X) |(X+X) ) ,4,6) ,-7) ) ) ) ,4) ) +transpose((transpose(transpose((echo(((transpose(X,-5) +transpose(transpose(X,4) ,4) ) +transpose((X+transpose(X,12) ) ,7) ) ,4,6) +transpose(transpose(((X+transpose(transpose(X,4) ,7) ) |transpose(X,-7) ) ,-5) ,12) ) ,4) ,-5) +transpose((((((transpose((X+X) ,4) +transpose(transpose(X,-7) ,-7) ) +transpose(transpose(arpeggio(X) ,4) ,12) ) |(shuffle(X) +transpose(transpose(X,-7) ,7) ) ) +transpose(arpeggio((transpose(transpose(X,4) ,4) +arpeggio((transpose(X,-7) +transpose(X,7) ) ) ) ) ,4) ) +transpose(step(transpose(((X+transpose(X,7) ) |echo(X,4,6) ) ,4) ,12) ,7) ) ,-7) ) ,7) ) ,7) ) ,-7) +transpose((((transpose(arpeggio(transpose((X+transpose((X+transpose((X+transpose(X,12) ) ,12) ) ,7) ) ,-7) ) ,4) |(transpose((transpose(arpeggio(transpose(transpose(X,-7) ,-7) ) ,4) +transpose((transpose(((X+transpose(X,12) ) +transpose(X,12) ) ,4) +transpose((transpose(X,-5) +transpose(X,7) ) ,7) ) ,7) ) ,4) |step(((shuffle((X+arpeggio(X) ) ) +transpose(transpose((transpose((X|X) ,4) +transpose((X+transpose(X,7) ) ,7) ) ,4) ,7) ) +(((shuffle(X) +transpose(((transpose((X+transpose(X,7) ) ,-5) +transpose(transpose(X,4) ,4) ) +transpose(arpeggio(transpose(X,-5) ) ,7) ) ,4) ) +transpose(echo((X+transpose(X,12) ) ,4,6) ,7) ) |(X|arpeggio(X) ) ) ) ,12) ) ) +(transpose(transpose(((transpose(transpose(X,-7) ,-7) +transpose(((X+transpose(X,12) ) +X) ,12) ) +transpose((X+X) ,12) ) ,-7) ,-7) +transpose(step(transpose(transpose(shuffle(transpose(transpose(X,-7) ,-5) ) ,4) ,-5) ,12) ,7) ) ) |transpose(transpose(arpeggio(shuffle(step(echo(echo(X,4,6) ,4,6) ,12) ) ) ,-7) ,4) ) ,7) ) ,-5) ) ,12) ) ,4,6)
random seed used was 147438543

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