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 19 generations the expression "X" became this:
arpeggio(echo(step(((((transpose(arpeggio(transpose(arpeggio(transpose(((((((transpose(X,-5) +transpose((X+transpose(X,7) ) ,4) ) +transpose((X+X) ,7) ) +step(X,12) ) |step(X,12) ) +transpose(transpose((transpose(X,4) +arpeggio(X) ) ,-7) ,4) ) +transpose(((((X+transpose(X,4) ) +transpose(X,7) ) |shuffle(X) ) +transpose((X+transpose(arpeggio(X) ,12) ) ,7) ) ,7) ) ,-7) ) ,4) ) ,-7) +transpose((step(shuffle((X+echo(((X+transpose(X,4) ) +transpose(X,7) ) ,4,6) ) ) ,12) |((((((echo(X,4,6) +transpose((X+X) ,7) ) |shuffle(X) ) +transpose((shuffle(echo(((transpose(step(X,12) ,-7) +transpose(arpeggio((X+transpose(X,7) ) ) ,4) ) +transpose((X+transpose(X,12) ) ,7) ) ,4,6) ) +step(step(((arpeggio(X) +(X+transpose(X,12) ) ) +transpose(transpose((X+transpose(X,7) ) ,4) ,7) ) ,12) ,12) ) ,4) ) +transpose(transpose((transpose(transpose(step(X,12) ,4) ,4) +transpose((shuffle((X+transpose(X,7) ) ) +transpose(transpose(step(X,12) ,4) ,12) ) ,7) ) ,-5) ,7) ) +transpose(transpose((echo(((echo(shuffle(X) ,4,6) +transpose(arpeggio(X) ,4) ) +transpose(step(echo(X,4,6) ,12) ,7) ) ,4,6) +arpeggio((((X+transpose(X,7) ) +transpose(transpose(X,-7) ,4) ) +transpose(((X|X) |X) ,7) ) ) ) ,4) ,7) ) |step(step(step(transpose(echo((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(X,12) ) ,4,6) ,4) ,12) ,12) ,12) ) ) ,4) ) +transpose(((((((transpose(X,-5) +transpose(X,7) ) |(X|X) ) +transpose(echo(step(X,12) ,4,6) ,4) ) +transpose(echo(transpose((X+transpose(X,7) ) ,-5) ,4,6) ,7) ) +transpose(shuffle(echo((X+(X+transpose(X,7) ) ) ,4,6) ) ,7) ) +transpose((echo(transpose(X,-5) ,4,6) |shuffle(transpose(transpose(transpose((((X+transpose(step(X,12) ,12) ) +transpose((X+transpose(X,-5) ) ,4) ) +transpose(X,7) ) ,-7) ,-5) ,4) ) ) ,7) ) ,7) ) +transpose((transpose(shuffle((transpose(transpose(transpose(arpeggio((((arpeggio(X) +((X+transpose(X,4) ) +transpose(X,7) ) ) +transpose(step(transpose(X,4) ,12) ,4) ) +transpose(transpose(X,4) ,7) ) ) ,4) ,-7) ,-7) +transpose(arpeggio(arpeggio(transpose((X|X) ,-7) ) ) ,7) ) ) ,-7) +transpose(transpose((shuffle(echo(step(((transpose((transpose(X,4) |(X+transpose(X,12) ) ) ,-5) +transpose(arpeggio(arpeggio((X+X) ) ) ,4) ) +transpose(shuffle((X|X) ) ,7) ) ,12) ,4,6) ) +transpose((((transpose((step(transpose(transpose(X,-5) ,4) ,12) +transpose(((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(echo(X,4,6) ,4) ) +transpose(X,7) ) ,7) ) ,-7) +transpose(((X+((X+transpose(X,4) ) +transpose(X,7) ) ) +transpose(echo(((((X+transpose(X,4) ) +transpose(X,7) ) +transpose((X|X) ,12) ) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) ,4,6) ,7) ) ,7) ) +transpose((((step((((X|X) +transpose((shuffle(X) |X) ,7) ) +transpose((transpose(step(X,12) ,4) +(echo(X,4,6) |(X+X) ) ) ,7) ) ,12) +transpose(transpose(((X|X) |X) ,-5) ,7) ) +transpose(transpose((X+transpose(X,7) ) ,-7) ,7) ) +transpose(echo(((arpeggio(X) +shuffle(step(X,12) ) ) +transpose(X,7) ) ,4,6) ,7) ) ,4) ) +transpose(((((((X+transpose(X,7) ) +X) +transpose(echo((X+X) ,4,6) ,12) ) +transpose(shuffle((transpose(((X+X) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) ,-7) +transpose(transpose(X,-5) ,12) ) ) ,4) ) +transpose((((echo(X,4,6) +transpose(transpose(X,4) ,4) ) +transpose(transpose(X,4) ,7) ) +transpose((arpeggio(X) |transpose(transpose((X|X) ,-5) ,4) ) ,12) ) ,7) ) +transpose(((echo(arpeggio(shuffle(X) ) ,4,6) +transpose(step(step(arpeggio(shuffle(X) ) ,12) ,12) ,4) ) +transpose(arpeggio(echo((X|X) ,4,6) ) ,7) ) ,7) ) ,7) ) ,7) ) ,-7) ,7) ) ,12) ) +(transpose(((arpeggio(arpeggio(shuffle((transpose(step(shuffle(X) ,12) ,-5) +(((echo(shuffle(X) ,4,6) +transpose(shuffle(X) ,4) ) +transpose(transpose(arpeggio(X) ,-7) ,7) ) |shuffle(((X+transpose(X,4) ) +transpose(X,7) ) ) ) ) ) ) ) +transpose(((echo(transpose(step(transpose((((X+transpose(X,12) ) +transpose(X,4) ) +transpose(X,7) ) ,4) ,12) ,4) ,4,6) +transpose(transpose(((step(X,12) +transpose(transpose(transpose(step(X,12) ,-5) ,-5) ,4) ) +transpose(((arpeggio(transpose((((X|X) +((X+transpose(X,4) ) +transpose(X,7) ) ) +transpose(X,-7) ) ,-7) ) +transpose(((transpose(transpose((transpose(X,4) +X) ,-5) ,4) +transpose(transpose(arpeggio(X) ,-7) ,7) ) |(transpose(X,4) +(shuffle((X+transpose(X,7) ) ) +transpose(step(((X+transpose(X,4) ) +transpose(X,7) ) ,12) ,7) ) ) ) ,4) ) +transpose(step(((X+transpose(step(X,12) ,7) ) +transpose((echo((X|X) ,4,6) +transpose(transpose(echo(((X+transpose(X,4) ) +transpose(X,7) ) ,4,6) ,-7) ,12) ) ,7) ) ,12) ,7) ) ,7) ) ,-5) ,4) ) +transpose((((((transpose((step(echo(X,4,6) ,12) +transpose(arpeggio((X+transpose(X,12) ) ) ,7) ) ,-5) +transpose(((echo(((X+transpose(X,4) ) +transpose(X,7) ) ,4,6) +transpose(echo(transpose((X+transpose(X,7) ) ,4) ,4,6) ,4) ) +transpose(((step(X,12) +transpose((X|X) ,4) ) +transpose(echo(X,4,6) ,7) ) ,7) ) ,4) ) +transpose((echo((transpose(X,4) |((X+transpose(X,7) ) +transpose(X,-7) ) ) ,4,6) |(transpose((X+transpose(X,7) ) ,-5) +transpose(((X+echo(X,4,6) ) +transpose(((echo(X,4,6) +transpose(transpose(X,4) ,4) ) +transpose((X+transpose(X,7) ) ,7) ) ,7) ) ,7) ) ) ,7) ) |shuffle(shuffle(transpose(X,-5) ) ) ) +shuffle((((shuffle(step(X,12) ) |echo(step((echo(X,4,6) +transpose(X,7) ) ,12) ,4,6) ) +transpose(((((((X+transpose(X,4) ) +transpose(X,7) ) +(X+X) ) +transpose((X+transpose(X,12) ) ,12) ) +transpose(transpose(shuffle((arpeggio(X) +((X+transpose(X,4) ) +transpose(X,7) ) ) ) ,-7) ,4) ) +transpose(transpose(((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(X,4) ) +transpose(arpeggio(X) ,7) ) ,-7) ,7) ) ,4) ) +transpose((echo((echo(X,4,6) +transpose(arpeggio(X) ,7) ) ,4,6) +echo(X,4,6) ) ,7) ) ) ) +transpose(echo(echo(transpose((step((X+transpose(X,7) ) ,12) +echo(X,4,6) ) ,-7) ,4,6) ,4,6) ,12) ) ,7) ) ,4) ) +transpose((((transpose(step(((step(X,12) |transpose(step(X,12) ,-7) ) |((transpose(transpose(X,4) ,4) +transpose(step(X,12) ,4) ) +transpose(step(arpeggio(X) ,12) ,7) ) ) ,12) ,-5) +transpose((transpose(transpose(step(X,12) ,-7) ,-5) |((transpose((X|(X|X) ) ,-7) +transpose((X+transpose((X+transpose(X,12) ) ,12) ) ,12) ) +transpose(shuffle(X) ,4) ) ) ,12) ) +transpose(echo(transpose(((step(transpose(((arpeggio(((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(step(X,12) ,4) ) +transpose(echo(X,4,6) ,7) ) ) +transpose(step(transpose(X,4) ,12) ,4) ) +transpose((step(X,12) +transpose(transpose(X,-7) ,12) ) ,7) ) ,-5) ,12) +transpose(transpose(arpeggio((echo(X,4,6) |(X+transpose(X,7) ) ) ) ,-5) ,4) ) +transpose(arpeggio(transpose(echo(((X+transpose(X,4) ) +transpose(X,7) ) ,4,6) ,-5) ) ,7) ) ,-5) ,4,6) ,7) ) |transpose(echo((((((X+transpose((X+X) ,4) ) +transpose(arpeggio(X) ,7) ) +transpose((transpose((X+X) ,4) +transpose((echo(X,4,6) +transpose(X,7) ) ,7) ) ,4) ) +transpose((((((X+X) +transpose(echo(X,4,6) ,4) ) +transpose((X+transpose(X,7) ) ,7) ) +transpose(((X+X) +transpose((X|X) ,12) ) ,4) ) +transpose(X,7) ) ,7) ) +(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-5) +transpose((X|arpeggio(arpeggio(X) ) ) ,7) ) ) ,4,6) ,4) ) ,7) ) ,-7) +transpose((((((echo(transpose(arpeggio(step(echo((X+X) ,4,6) ,12) ) ,-5) ,4,6) +arpeggio(step((transpose(((X+transpose((X+transpose(X,12) ) ,7) ) |shuffle(step(X,12) ) ) ,-7) +transpose((X+transpose(arpeggio(echo(shuffle(X) ,4,6) ) ,7) ) ,7) ) ,12) ) ) |transpose((((step(shuffle(arpeggio(X) ) ,12) +transpose((arpeggio((X+transpose(X,12) ) ) +transpose(echo(echo(arpeggio(X) ,4,6) ,4,6) ,7) ) ,7) ) +transpose(step(transpose(((step((X|X) ,12) +transpose(((echo((X|X) ,4,6) +transpose(transpose(X,-7) ,4) ) +transpose(transpose(X,-5) ,7) ) ,4) ) +transpose(X,7) ) ,-7) ,12) ,4) ) +transpose(shuffle((transpose(arpeggio(echo((X+transpose(X,7) ) ,4,6) ) ,-7) |transpose((echo(X,4,6) +echo(X,4,6) ) ,-5) ) ) ,7) ) ,-7) ) +transpose(transpose(transpose(((shuffle((((transpose(X,-5) +transpose(X,7) ) +transpose(echo((X|X) ,4,6) ,4) ) +transpose((X+X) ,7) ) ) |((transpose(transpose(X,-5) ,4) +transpose(transpose((X+transpose(X,7) ) ,-5) ,4) ) +transpose((arpeggio(transpose(X,4) ) +transpose((X|X) ,7) ) ,7) ) ) |((transpose(transpose(((X+transpose(X,12) ) +(X+transpose(transpose(X,-7) ,7) ) ) ,4) ,4) +transpose(step(arpeggio(X) ,12) ,4) ) +transpose((((transpose(X,4) +(X+transpose(X,12) ) ) +transpose(transpose(echo(X,4,6) ,4) ,12) ) |(X+transpose(arpeggio(X) ,7) ) ) ,7) ) ) ,-5) ,-7) ,7) ) +transpose(echo(((((shuffle(X) +transpose(arpeggio(arpeggio((X+transpose(X,12) ) ) ) ,7) ) |transpose((echo(((transpose(X,-5) +shuffle(X) ) +echo(step(transpose(X,-7) ,12) ,4,6) ) ,4,6) +transpose(step((step(X,12) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) ,12) ,12) ) ,4) ) +transpose(((((transpose(shuffle(((X+transpose(X,4) ) +transpose(X,7) ) ) ,-7) +transpose(((((X+transpose(X,4) ) +transpose(X,7) ) +transpose((X+transpose(X,7) ) ,7) ) +((transpose(X,-5) +transpose(transpose(X,-7) ,4) ) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) ) ,7) ) +shuffle(transpose((echo(X,4,6) |X) ,-7) ) ) +transpose((X+transpose((X|X) ,4) ) ,4) ) +transpose(((((((step(X,12) +transpose((X+transpose(X,7) ) ,7) ) +transpose(transpose(X,-5) ,4) ) +transpose(X,7) ) +transpose(shuffle((echo((X+transpose(X,7) ) ,4,6) +transpose(((X+transpose(X,7) ) |X) ,7) ) ) ,7) ) +transpose(shuffle((((X+transpose(X,4) ) +transpose(X,7) ) |echo(X,4,6) ) ) ,4) ) +transpose((transpose(step(X,12) ,4) +transpose(step((step(echo(X,4,6) ,12) +transpose((((X+transpose(X,12) ) +transpose(shuffle(X) ,4) ) +transpose(X,7) ) ,7) ) ,12) ,12) ) ,7) ) ,7) ) ,4) ) +transpose(arpeggio((shuffle(echo(step(transpose(arpeggio((X|X) ) ,-7) ,12) ,4,6) ) |shuffle((arpeggio(((X+transpose(X,4) ) +transpose(X,7) ) ) +transpose(shuffle(X) ,12) ) ) ) ) ,7) ) ,4,6) ,4) ) +transpose(transpose(step(arpeggio(arpeggio(((X+X) |arpeggio((X+transpose(X,7) ) ) ) ) ) ,12) ,-5) ,7) ) ,12) ) ) ,12) ,4,6) )
random seed used was 238954993

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