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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After 18 generations the expression "X" became this:
(((((transpose((transpose((echo(X,4,6) +transpose(arpeggio(X) ,12) ) ,4) +transpose(transpose((transpose(X,-7) +X) ,-5) ,7) ) ,-7) +transpose(transpose(transpose(transpose(((step((transpose(X,-7) +((X+transpose(X,12) ) +(X+transpose(X,7) ) ) ) ,12) +transpose(((transpose((X+transpose(X,7) ) ,-7) |(transpose(X,4) +shuffle(X) ) ) +transpose(transpose((((transpose(X,4) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) ) +transpose(echo(X,4,6) ,7) ) |arpeggio((X+transpose(X,12) ) ) ) ,-7) ,7) ) ,7) ) +transpose(transpose((((X|X) +transpose((transpose(X,-5) |transpose(X,-5) ) ,4) ) +transpose((X+X) ,7) ) ,4) ,-7) ) ,4) ,4) ,-5) ,4) ) +transpose((step(step((echo(X,4,6) |((X+transpose(X,4) ) +transpose(X,7) ) ) ,12) ,12) |echo((transpose((X+transpose(X,7) ) ,-7) +transpose(transpose((((X+X) |(X+X) ) |(((X+transpose(X,4) ) +transpose(X,7) ) +transpose(X,4) ) ) ,-5) ,12) ) ,4,6) ) ,7) ) |(((transpose(transpose((echo(transpose(X,-7) ,4,6) +transpose(transpose(transpose(arpeggio((X+X) ) ,-7) ,4) ,12) ) ,4) ,-5) +transpose(transpose((((transpose(((transpose(transpose(X,-5) ,-5) +(X|X) ) |transpose((X+X) ,4) ) ,-7) +transpose(step((transpose(X,-5) +step((transpose(X,4) +transpose(X,7) ) ,12) ) ,12) ,12) ) |(echo(transpose(transpose(X,-7) ,4) ,4,6) +arpeggio(((X+transpose(X,4) ) +transpose(X,7) ) ) ) ) +transpose(echo((((step(X,12) +transpose((X+X) ,7) ) +transpose(((X+transpose(X,7) ) +transpose(X,7) ) ,12) ) +transpose(((((X+transpose(X,7) ) |X) +transpose((X+transpose(X,12) ) ,7) ) +X) ,-7) ) ,4,6) ,12) ) ,4) ,4) ) +transpose(echo((transpose(((echo(transpose(X,-7) ,4,6) |step(echo(transpose((X+transpose((X|X) ,7) ) ,-5) ,4,6) ,12) ) |shuffle((echo(X,4,6) +(X|(((X+transpose(X,4) ) +transpose(X,7) ) +transpose((X+transpose(X,12) ) ,12) ) ) ) ) ) ,-5) +step((((step(((X+(X+X) ) +(transpose(X,4) +transpose(step(X,12) ,7) ) ) ,12) |(step(transpose((X+X) ,-7) ,12) +transpose(shuffle((transpose(X,-7) |transpose(X,-7) ) ) ,7) ) ) +transpose(((transpose(transpose(X,4) ,4) +transpose(transpose(((transpose(X,-5) +transpose(echo(X,4,6) ,12) ) +X) ,4) ,7) ) +transpose(((X+transpose(X,12) ) +transpose(((transpose(X,-7) +transpose(transpose(X,-7) ,4) ) +transpose((X+transpose(X,7) ) ,7) ) ,12) ) ,-7) ) ,4) ) +transpose(((transpose(transpose(arpeggio(X) ,4) ,-5) +transpose(transpose(X,4) ,4) ) +transpose(transpose(transpose(transpose(X,-5) ,-5) ,4) ,7) ) ,7) ) ,12) ) ,4,6) ,7) ) +transpose(((((((((step(transpose(X,-7) ,12) +transpose(((X+transpose(X,12) ) +transpose(shuffle(X) ,12) ) ,12) ) +transpose(shuffle((X+(arpeggio(X) +(X+transpose(X,7) ) ) ) ) ,4) ) +transpose(transpose(shuffle((step(X,12) +shuffle(X) ) ) ,4) ,7) ) |(transpose(((transpose(X,4) |X) +transpose(arpeggio(arpeggio(arpeggio(X) ) ) ,7) ) ,-7) +transpose(transpose(transpose(transpose(X,-5) ,4) ,-7) ,7) ) ) +transpose(((X+transpose(X,12) ) |X) ,4) ) +transpose(transpose((((X+transpose(X,12) ) +transpose((((shuffle((X+transpose(X,12) ) ) |(X+X) ) +transpose(((X+X) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,12) ) ,4) ) +transpose((((transpose(X,-5) |transpose(X,4) ) +transpose(X,4) ) +transpose(transpose(X,4) ,7) ) ,7) ) ,12) ) |(echo((step(X,12) +transpose(transpose(X,4) ,7) ) ,4,6) |arpeggio((X+transpose(X,12) ) ) ) ) ,-7) ,7) ) +transpose(transpose(((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(transpose(X,-5) ,12) ) +transpose(((X+transpose(X,7) ) |X) ,7) ) ,4) ,4) ) +transpose((transpose(echo(echo(transpose(transpose(transpose(arpeggio((X+transpose((X+transpose(X,12) ) ,7) ) ) ,-5) ,-7) ,4) ,4,6) ,4,6) ,-5) |((((transpose(((((((X|X) +transpose(X,-7) ) +transpose((X+transpose(transpose(X,-5) ,12) ) ,12) ) |transpose(echo(X,4,6) ,4) ) +arpeggio((transpose(transpose(X,-7) ,4) |(transpose(echo(X,4,6) ,4) +((X+transpose(X,4) ) +transpose(X,7) ) ) ) ) ) +transpose(shuffle(transpose(((X|transpose(transpose(X,4) ,-7) ) +echo(step(X,12) ,4,6) ) ,4) ) ,7) ) ,-5) +transpose((((arpeggio((transpose(X,-7) +X) ) |transpose((X|X) ,4) ) |(((transpose((X+transpose(X,7) ) ,-7) +transpose(transpose(arpeggio(X) ,-7) ,7) ) +(echo(X,4,6) |transpose((X|X) ,4) ) ) |shuffle(transpose((X+transpose(transpose(X,-7) ,12) ) ,-5) ) ) ) +transpose(shuffle(transpose(transpose(X,-5) ,4) ) ,7) ) ,12) ) +transpose(transpose((transpose((((X+transpose(transpose(X,-5) ,12) ) +transpose(shuffle(transpose(X,-5) ) ,4) ) +transpose((transpose(X,-7) +transpose((X+transpose(X,7) ) ,7) ) ,7) ) ,-7) |arpeggio((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(X,12) ) ) ) ,-7) ,4) ) +transpose(echo(shuffle(echo(step((echo(X,4,6) +transpose(X,7) ) ,12) ,4,6) ) ,4,6) ,7) ) +((step(transpose(X,-5) ,12) |X) +transpose(transpose((arpeggio(((X+transpose((X+X) ,4) ) +transpose((X+X) ,7) ) ) +((transpose(transpose(transpose(X,-5) ,-7) ,-7) +transpose(((step(X,12) +transpose(transpose(X,4) ,7) ) |X) ,12) ) +transpose(transpose(((X|X) |transpose(X,4) ) ,-5) ,7) ) ) ,4) ,12) ) ) ) ,7) ) ,12) ) ) +transpose((step(transpose((transpose(shuffle(step((shuffle(((X+transpose(X,7) ) +transpose(X,7) ) ) +transpose(shuffle(arpeggio(transpose(X,4) ) ) ,7) ) ,12) ) ,-7) |transpose(((transpose(((transpose(transpose(transpose(transpose(X,-5) ,-7) ,-7) ,-7) +transpose(transpose(transpose(transpose((X|X) ,-5) ,-7) ,-5) ,4) ) +transpose(((transpose(X,-7) +transpose(transpose((transpose(X,-5) +transpose(shuffle(X) ,12) ) ,4) ,7) ) +(X+X) ) ,7) ) ,4) +transpose(((transpose((transpose(X,4) +X) ,-5) |transpose(echo((X+X) ,4,6) ,4) ) +transpose((transpose(shuffle(transpose(((X+transpose(X,12) ) |(X+transpose(X,7) ) ) ,4) ) ,-5) +((transpose(transpose(X,4) ,-7) +(X|X) ) |transpose(transpose(transpose(X,-5) ,4) ,-7) ) ) ,7) ) ,7) ) +transpose(transpose((transpose(X,4) +(X+X) ) ,-7) ,-7) ) ,-5) ) ,4) ,12) |((((transpose(transpose(transpose(transpose(X,4) ,4) ,-7) ,4) |transpose((transpose(X,-5) +transpose((((transpose((X+transpose(arpeggio(X) ,12) ) ,4) +(((transpose((X|transpose(X,-5) ) ,-5) |((X|X) |(X|X) ) ) +transpose(((X|X) +transpose((X|X) ,12) ) ,4) ) +transpose(step(transpose(X,-5) ,12) ,7) ) ) +transpose(((echo(((X+X) |transpose(X,-7) ) ,4,6) |transpose(transpose((X|X) ,-5) ,-7) ) +transpose(transpose(transpose((transpose(transpose(X,4) ,4) +transpose(((X|X) +transpose(((transpose(X,4) +transpose((X+transpose(X,12) ) ,4) ) +transpose(X,7) ) ,12) ) ,7) ) ,-7) ,-7) ,12) ) ,4) ) +transpose(transpose(arpeggio((arpeggio((X+transpose(X,-5) ) ) +((transpose(transpose(X,-7) ,-7) +transpose((transpose((X+transpose(X,7) ) ,-7) +(X+transpose(X,-5) ) ) ,4) ) +transpose(X,7) ) ) ) ,-7) ,7) ) ,7) ) ,-5) ) +transpose(transpose(((echo((shuffle(((transpose(((arpeggio(X) +X) +((X+transpose(X,4) ) +transpose(X,7) ) ) ,-7) +transpose(arpeggio(X) ,4) ) +transpose(transpose(transpose((transpose(transpose(X,-7) ,-7) +(X|X) ) ,4) ,-7) ,7) ) ) |((transpose(transpose((X+X) ,4) ,-5) +transpose(echo(transpose(X,-7) ,4,6) ,-7) ) +echo(transpose(((X|X) +transpose(transpose(X,4) ,7) ) ,4) ,4,6) ) ) ,4,6) +transpose(transpose(transpose(step(step(transpose(transpose(transpose(X,-7) ,4) ,4) ,12) ,12) ,-7) ,4) ,12) ) +transpose(((((echo(((((X+transpose((((X+transpose(X,7) ) +transpose(transpose(X,-5) ,4) ) +transpose((X+X) ,7) ) ,12) ) |transpose(echo(X,4,6) ,4) ) +transpose(step(((X+transpose(X,4) ) +transpose(X,7) ) ,12) ,4) ) +transpose(transpose(transpose((shuffle(X) +transpose(X,7) ) ,-7) ,-7) ,7) ) ,4,6) +transpose(transpose(transpose(echo(transpose(transpose((X+transpose(X,12) ) ,-5) ,4) ,4,6) ,-5) ,-5) ,4) ) +transpose(((transpose(arpeggio(((X+transpose(X,12) ) +transpose(X,12) ) ) ,4) +transpose((transpose(shuffle(X) ,-5) +transpose(((transpose(X,-5) +transpose(X,7) ) +transpose(step(X,12) ,-5) ) ,7) ) ,4) ) |arpeggio(((X+transpose(echo(X,4,6) ,12) ) +transpose(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-7) ,12) ) ) ) ,7) ) |(((((arpeggio(transpose(X,4) ) +transpose(transpose(transpose(X,-7) ,4) ,4) ) +transpose(transpose(X,-5) ,7) ) +transpose((step(X,12) +transpose((X+X) ,12) ) ,4) ) +transpose(X,7) ) +transpose(echo(X,4,6) ,4) ) ) |echo(transpose((((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(X,4) ) +transpose(X,7) ) +transpose((X|X) ,12) ) ,4) ,4,6) ) ,7) ) ,-7) ,4) ) +transpose((((step(echo(((transpose(X,-5) +transpose(transpose(X,-5) ,4) ) +transpose(arpeggio(X) ,7) ) ,4,6) ,12) +(((echo(((X+transpose(transpose(X,-5) ,4) ) +transpose(echo(X,4,6) ,7) ) ,4,6) +shuffle((echo(transpose(X,4) ,4,6) |(((X+transpose(X,4) ) +transpose(X,7) ) +transpose(X,4) ) ) ) ) +transpose(transpose(((transpose(X,4) |(transpose(X,-7) +transpose(X,7) ) ) +transpose((transpose((((X+transpose((X|X) ,7) ) +transpose(shuffle(transpose(X,-5) ) ,4) ) +transpose(X,7) ) ,4) +transpose(((((X+transpose((X|X) ,4) ) +transpose(arpeggio(X) ,7) ) |transpose(X,-5) ) |(X+transpose((X+transpose(X,7) ) ,7) ) ) ,12) ) ,12) ) ,-7) ,7) ) +transpose(echo(arpeggio((transpose(transpose((X+transpose(transpose(X,-7) ,12) ) ,-5) ,4) +transpose(shuffle(X) ,4) ) ) ,4,6) ,7) ) ) +transpose(transpose((transpose((transpose(step((transpose(transpose(X,-5) ,-5) |transpose((X+transpose(X,4) ) ,-7) ) ,12) ,4) +((step(arpeggio((X+X) ) ,12) +transpose((transpose(step((X+X) ,12) ,4) |((transpose(shuffle(X) ,4) +transpose(transpose(X,-5) ,12) ) +transpose(transpose(X,4) ,7) ) ) ,7) ) +transpose((transpose(X,4) |((shuffle(X) |(X+transpose(X,7) ) ) +(X|transpose(X,-5) ) ) ) ,7) ) ) ,-5) +(transpose(arpeggio((transpose(X,4) +X) ) ,4) +transpose(((X|X) +(arpeggio(X) |transpose(X,4) ) ) ,12) ) ) ,-7) ,7) ) |transpose(((step(((echo((X+X) ,4,6) +transpose(step(X,12) ,7) ) +transpose(step((X+transpose((echo(X,4,6) |(X+X) ) ,7) ) ,12) ,12) ) ,12) +transpose((transpose(transpose(((X|((X+X) +X) ) +((X+X) |(X+transpose(transpose(X,-5) ,12) ) ) ) ,-5) ,-5) +transpose((transpose(shuffle(transpose(transpose(X,4) ,-7) ) ,-7) +transpose(((echo(X,4,6) +transpose(X,12) ) |(transpose(X,4) |(X+shuffle(X) ) ) ) ,-7) ) ,-5) ) ,7) ) +transpose((echo((transpose((step(X,12) +transpose(arpeggio((transpose(X,-5) +transpose(transpose(X,-5) ,7) ) ) ,7) ) ,4) |transpose(transpose(X,-5) ,4) ) ,4,6) |transpose(step((((transpose(echo(X,4,6) ,-5) +transpose(transpose(step(X,12) ,-7) ,7) ) +transpose((transpose(X,-5) |((X+transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) ) +transpose(X,7) ) ) ,12) ) +transpose(transpose(X,4) ,12) ) ,12) ,4) ) ,7) ) ,-7) ) ,7) ) +transpose(transpose(step((arpeggio(shuffle((shuffle((X+transpose((shuffle(X) +(transpose(X,-5) |step(X,12) ) ) ,12) ) ) +transpose(((transpose((transpose(shuffle(X) ,-5) +transpose((X+transpose(X,7) ) ,7) ) ,4) +transpose(transpose(((transpose((X|X) ,4) +transpose(transpose(X,-7) ,12) ) +transpose((X|X) ,7) ) ,-7) ,4) ) +transpose((transpose(((X+transpose(transpose(X,-5) ,4) ) +transpose(X,7) ) ,-7) +(transpose((X|X) ,4) +transpose(transpose(X,-5) ,7) ) ) ,7) ) ,7) ) ) ) |transpose(echo(((step(transpose((((step(X,12) +transpose(X,12) ) |(X|X) ) |transpose(transpose(X,4) ,4) ) ,-7) ,12) |(transpose((echo(X,4,6) +transpose(transpose(transpose(X,-5) ,4) ,7) ) ,-7) |(transpose(X,4) |X) ) ) |transpose(transpose(transpose(((X+echo(X,4,6) ) |(X+X) ) ,4) ,-7) ,-7) ) ,4,6) ,4) ) ,12) ,4) ,12) ) ) ,4) ) +transpose(arpeggio((step((shuffle(transpose(transpose(arpeggio(X) ,4) ,-5) ) +transpose((step((transpose(transpose(X,-5) ,-7) +transpose((((X+transpose(X,12) ) |echo(X,4,6) ) +transpose(transpose(arpeggio(X) ,4) ,12) ) ,12) ) ,12) +((((transpose(step(X,12) ,-7) +transpose(X,4) ) |(transpose((shuffle(X) +transpose(transpose(X,4) ,7) ) ,4) |echo((transpose(X,-5) +transpose(X,12) ) ,4,6) ) ) |shuffle(((X+(X+X) ) +echo(transpose(X,-7) ,4,6) ) ) ) +((((echo(((X+X) +transpose(shuffle(X) ,12) ) ,4,6) +transpose(echo(X,4,6) ,12) ) +transpose(((transpose(shuffle((X|X) ) ,-7) +transpose(((arpeggio(X) +transpose(X,7) ) +(X+transpose(X,7) ) ) ,4) ) +transpose(transpose((X+X) ,4) ,7) ) ,12) ) +transpose(((X|step(X,12) ) +transpose(echo(transpose(X,4) ,4,6) ,7) ) ,4) ) +transpose((((X+transpose(X,7) ) +transpose((X+X) ,12) ) |shuffle((transpose(X,-5) +transpose(transpose(X,4) ,7) ) ) ) ,7) ) ) ) ,12) ) ,12) |(((transpose(echo(X,4,6) ,4) |transpose(step((transpose(arpeggio((X+X) ) ,4) +arpeggio(transpose((X+transpose(X,7) ) ,-5) ) ) ,12) ,-5) ) +transpose((step(step(transpose(shuffle(X) ,-7) ,12) ,12) +(((arpeggio(transpose(arpeggio(X) ,4) ) +(transpose(X,-7) +(X|shuffle(X) ) ) ) +transpose(transpose(X,-7) ,4) ) +transpose(transpose(X,-7) ,7) ) ) ,7) ) +transpose(((echo((((transpose(X,-5) |transpose((transpose(X,-7) +shuffle(arpeggio(X) ) ) ,4) ) +transpose(transpose(transpose((shuffle(X) |transpose(X,-7) ) ,-7) ,-5) ,-5) ) +shuffle((((X|X) |(X|X) ) |((transpose(X,4) +(X+transpose(X,12) ) ) |X) ) ) ) ,4,6) +transpose(((arpeggio(transpose((transpose(shuffle(X) ,-5) +transpose(arpeggio(((X+transpose(X,4) ) +transpose(X,7) ) ) ,7) ) ,-7) ) +transpose((transpose(transpose((transpose(X,-7) +transpose((X+transpose(X,7) ) ,12) ) ,-5) ,-5) |(step(transpose((X|X) ,-5) ,12) |((X|step(arpeggio(X) ,12) ) +transpose(transpose(transpose(step(X,12) ,-5) ,4) ,12) ) ) ) ,4) ) +transpose(echo(step(((((step(X,12) +transpose((X+transpose(X,7) ) ,4) ) +transpose(X,7) ) +transpose(echo(X,4,6) ,-5) ) +transpose((arpeggio(X) +transpose(shuffle(step(X,12) ) ,12) ) ,7) ) ,12) ,4,6) ,7) ) ,4) ) +transpose(transpose((((transpose((echo(X,4,6) +transpose(X,-7) ) ,4) +transpose((X+transpose(((X+X) +transpose(X,-5) ) ,7) ) ,4) ) +transpose(step(X,12) ,7) ) +transpose(step((transpose(X,-5) +(step((X|X) ,12) +transpose((X+transpose((X|echo(X,4,6) ) ,7) ) ,12) ) ) ,12) ,12) ) ,-7) ,7) ) ,12) ) ) ) ,7) )
random seed used was 36533249

NOTE: Generated phrase was too large ( 6964 ) , it has been truncated at 5000 notes. EXPR = transpose(transpose(((transpose(transpose(transpose((arpeggio(arpeggio(transpose(X,-5) ) ) +transpose(((X+((X|X) +transpose(X,7) ) ) +transpose(shuffle(echo(X,4,6) ) ,7) ) ,4) ) ,4) ,4) ,-7) +transpose(shuffle(((step(echo(transpose(((((X+X) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,12) ) +(transpose(X,-7) |step(X,12) ) ) |((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(transpose(X,-7) ,4) ) +transpose(transpose(X,-5) ,7) ) ) ,4) ,4,6) ,12) +transpose(((echo(X,4,6) +((shuffle(arpeggio(X) ) +X) |((X+transpose(shuffle(X) ,4) ) +transpose((X+transpose(X,7) ) ,7) ) ) ) +transpose(step(shuffle(X) ,12) ,12) ) ,-5) ) +transpose((step(transpose(arpeggio((X+transpose(transpose(X,-7) ,12) ) ) ,4) ,12) +transpose(arpeggio(echo(X,4,6) ) ,12) ) ,-5) ) ) ,4) ) +transpose(transpose((((arpeggio(step(step(echo(transpose(arpeggio(arpeggio(X) ) ,4) ,4,6) ,12) ,12) ) +transpose(arpeggio((((transpose((arpeggio(step((X+transpose(X,12) ) ,12) ) +(echo((X+X) ,4,6) +transpose(transpose(transpose(X,4) ,-5) ,7) ) ) ,4) +transpose(transpose(transpose(echo(X,4,6) ,-7) ,4) ,4) ) +transpose(transpose((((((X+transpose(transpose(X,4) ,4) ) +transpose(transpose(X,-5) ,7) ) +transpose((X+transpose(X,7) ) ,4) ) +(X+transpose(X,12) ) ) +transpose(((transpose(X,-5) |X) +transpose((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(X,12) ) ,7) ) ,7) ) ,4) ,7) ) |(((echo(((((X|X) +transpose(echo(X,4,6) ,4) ) +transpose(X,7) ) +transpose(((X|X) +(X+X) ) ,12) ) ,4,6) |(echo(((X+transpose(transpose(X,4) ,4) ) +transpose(echo(X,4,6) ,7) ) ,4,6) +transpose(transpose((X|step(X,12) ) ,4) ,12) ) ) +transpose(transpose(step((X+X) ,12) ,-5) ,4) ) |transpose(transpose(((X+X) +transpose(transpose((X+transpose(X,7) ) ,-7) ,12) ) ,4) ,-5) ) ) ) ,4) ) +transpose(step(transpose((((transpose(transpose((shuffle(X) +transpose(X,4) ) ,4) ,-5) +transpose(transpose(X,-5) ,4) ) +transpose(transpose(X,-5) ,7) ) +transpose(step(X,12) ,12) ) ,-5) ,12) ,7) ) +transpose(transpose(((((((step(X,12) +transpose(arpeggio((echo(X,4,6) +transpose(X,12) ) ) ,7) ) +(X|X) ) |((arpeggio(X) |transpose((X+(X+X) ) ,-5) ) +transpose(step((X|arpeggio(echo(X,4,6) ) ) ,12) ,7) ) ) +transpose(transpose(transpose(((((X+transpose(X,7) ) +transpose(step(X,12) ,4) ) +transpose(transpose(X,4) ,7) ) |echo(transpose(X,4) ,4,6) ) ,-5) ,-7) ,4) ) +transpose(((transpose(X,4) +transpose(transpose((echo(X,4,6) |((X+transpose(X,4) ) +transpose(X,7) ) ) ,4) ,-5) ) |transpose(transpose(X,4) ,4) ) ,7) ) |transpose(transpose((transpose((transpose(X,4) +transpose(transpose(X,-5) ,12) ) ,4) +transpose(((((X+X) |arpeggio(X) ) |X) |(transpose(step(X,12) ,-7) |echo(arpeggio(X) ,4,6) ) ) ,7) ) ,-7) ,4) ) ,-5) ,7) ) ,4) ,7) ) ,-7) ,-5)
random seed used was 0


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