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:
 Seed: Randomize seed: Generations: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Phrase for X: Basic 1 - c,e,gBasic 2 - c,g,e,b-Basic 3 - c,gBasic 4 - cBasic 5 - co3,co4,co3,co2Chord 1 - c e gChord 2 - c e- gChord 3 - c e- g b-Chord 4 - c f gFile 1 - bachinv1.midFile 2 - bachinv2.midFile 3 - bachinv3.midFile 4 - bachinv4.midFile 5 - bachinv5.midFile 6 - bachinv6.midFile 7 - bachinv7.midFile 8 - bachinv8.mid # of Tracks: 1234 Randomize patches: noyes Results may not appear for a few seconds.Be patient!
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 After 20 generations the expression "X" became this: (((transpose(shuffle((((((step((X|transpose(X,-5) ) ,12) +transpose(transpose((((X+transpose(transpose(X,4) ,4) ) +transpose(((arpeggio(X) +transpose(X,4) ) +transpose(shuffle(X) ,7) ) ,7) ) |((X+transpose(X,12) ) +transpose(X,7) ) ) ,-7) ,12) ) |((echo(shuffle(X) ,4,6) |echo(transpose(X,4) ,4,6) ) |((step(transpose(transpose(X,-7) ,-7) ,12) |transpose(transpose(shuffle(X) ,4) ,-5) ) +((((X+transpose(X,4) ) +transpose(X,7) ) |arpeggio(transpose(X,4) ) ) +transpose(((X+X) |transpose(step(X,12) ,4) ) ,12) ) ) ) ) +transpose(transpose(transpose((transpose(X,4) +transpose(shuffle((X+transpose(X,12) ) ) ,12) ) ,-5) ,4) ,7) ) |(transpose(X,-7) +transpose(((((((X+transpose(step(transpose(X,-7) ,12) ,4) ) +transpose(echo(transpose(X,-7) ,4,6) ,7) ) +transpose(arpeggio((((X+transpose(X,7) ) +transpose(step(X,12) ,4) ) +transpose(X,7) ) ) ,4) ) +transpose((transpose(transpose(X,-7) ,-5) +transpose(transpose(X,4) ,12) ) ,7) ) |(X+X) ) |(echo(step(X,12) ,4,6) +transpose((((transpose(X,-7) +transpose(arpeggio(X) ,4) ) +transpose(transpose(X,4) ,7) ) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-5) ) ,12) ) ) ,12) ) ) +transpose(echo(step((((echo(X,4,6) +transpose(arpeggio(transpose(arpeggio(X) ,-5) ) ,7) ) +transpose((((transpose((X+transpose(arpeggio(X) ,7) ) ,-7) |arpeggio(transpose(X,-5) ) ) +transpose((transpose((X+transpose(X,7) ) ,-5) +transpose(shuffle(X) ,12) ) ,4) ) +transpose(arpeggio(transpose(transpose(X,-7) ,-7) ) ,7) ) ,7) ) +transpose(((((X+transpose(echo(X,4,6) ,4) ) +transpose(X,7) ) +transpose((step(X,12) +shuffle(X) ) ,4) ) +transpose(transpose(X,4) ,7) ) ,7) ) ,12) ,4,6) ,7) ) ) ,-7) |(echo((shuffle(((((arpeggio((arpeggio((X|X) ) +transpose(transpose(echo(transpose(transpose(X,4) ,4) ,4,6) ,-7) ,12) ) ) |transpose(transpose((X+transpose(X,7) ) ,-7) ,4) ) +transpose((((((transpose(transpose((X|((X+transpose(X,4) ) +transpose(X,7) ) ) ,-5) ,4) |echo((X+(X|X) ) ,4,6) ) +echo((X|X) ,4,6) ) +transpose(transpose((echo(X,4,6) +((X+X) |(X+X) ) ) ,-7) ,4) ) +transpose(transpose(shuffle(step(transpose(X,4) ,12) ) ,-7) ,7) ) +transpose((echo(echo((((X+X) |X) +(X+X) ) ,4,6) ,4,6) |transpose(X,4) ) ,12) ) ,4) ) +transpose(((((((transpose(transpose(X,-5) ,-5) +transpose(transpose(transpose(X,4) ,-7) ,7) ) +transpose((arpeggio(transpose(X,-5) ) |((X+transpose(transpose(X,-5) ,4) ) +transpose(X,7) ) ) ,4) ) +transpose((((((X+transpose(X,7) ) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,12) ) +transpose(echo(X,4,6) ,4) ) +transpose((echo(X,4,6) |step(X,12) ) ,7) ) |arpeggio(transpose(transpose(X,4) ,4) ) ) ,7) ) +transpose(arpeggio((((((X+transpose(X,4) ) +transpose(X,7) ) |shuffle(X) ) +transpose(transpose(transpose(X,4) ,4) ,4) ) +transpose(X,7) ) ) ,4) ) +transpose((transpose(X,-5) +transpose(transpose(shuffle((X|X) ) ,4) ,12) ) ,7) ) |transpose(((transpose(X,4) |transpose(X,-5) ) +(shuffle(X) |shuffle(transpose(X,-5) ) ) ) ,-5) ) ,7) ) |((arpeggio((((X|X) +transpose((transpose(X,4) +arpeggio(X) ) ,4) ) +transpose(X,7) ) ) +transpose(transpose(transpose((X|X) ,4) ,-5) ,-7) ) +transpose((echo(((shuffle((X|X) ) |shuffle(X) ) +transpose(((echo(X,4,6) +transpose((echo(X,4,6) +transpose(arpeggio((X|X) ) ,12) ) ,4) ) +transpose(transpose(arpeggio(X) ,-5) ,7) ) ,12) ) ,4,6) +transpose(shuffle(transpose(echo(transpose(X,4) ,4,6) ,-7) ) ,12) ) ,7) ) ) ) |step(transpose(step(step(((transpose(transpose(X,-7) ,-5) +(transpose(transpose(X,-5) ,4) +transpose((X|X) ,12) ) ) |transpose(echo(echo(X,4,6) ,4,6) ,-5) ) ,12) ,12) ,4) ,12) ) ,4,6) +transpose((transpose((((shuffle((transpose(X,4) |arpeggio(X) ) ) +transpose(arpeggio((X+transpose(X,7) ) ) ,12) ) +transpose(shuffle(shuffle((X|X) ) ) ,4) ) +transpose(arpeggio(transpose((X+X) ,-7) ) ,7) ) ,-5) +((step(arpeggio(step(transpose(transpose((((X+transpose(X,4) ) +transpose(X,7) ) |step(X,12) ) ,4) ,-7) ,12) ) ,12) +transpose(arpeggio(((step(transpose(transpose(transpose(transpose(transpose(X,-5) ,4) ,4) ,-7) ,-7) ,12) +transpose((transpose(arpeggio(transpose(X,-5) ) ,-7) |transpose(transpose(((X+transpose(step(X,12) ,4) ) +transpose((X+transpose(X,12) ) ,7) ) ,-5) ,-7) ) ,-7) ) |transpose(((transpose((transpose(X,4) +transpose(((X|X) +transpose(X,12) ) ,7) ) ,-5) +step(transpose(transpose(echo(step(X,12) ,4,6) ,-7) ,-7) ,12) ) +transpose((transpose(((transpose(shuffle(X) ,-7) +transpose(step(step(X,12) ,12) ,4) ) +transpose((shuffle(X) +transpose(echo(shuffle(X) ,4,6) ,7) ) ,7) ) ,-5) |echo(echo(X,4,6) ,4,6) ) ,7) ) ,-5) ) ) ,7) ) +transpose((transpose(arpeggio(((transpose(transpose(X,-5) ,-5) +transpose(shuffle(X) ,4) ) +transpose(step((transpose(transpose(step(X,12) ,4) ,4) |transpose(step(echo(X,4,6) ,12) ,-7) ) ,12) ,12) ) ) ,-5) +transpose(echo((transpose(arpeggio(transpose(transpose(((shuffle(arpeggio(arpeggio(((echo(X,4,6) +transpose(X,4) ) +transpose(transpose(X,-7) ,7) ) ) ) ) +transpose(((transpose(echo(transpose(X,4) ,4,6) ,4) +transpose((X|arpeggio(X) ) ,7) ) +transpose(echo(step(arpeggio(shuffle(X) ) ,12) ,4,6) ,7) ) ,4) ) +transpose(transpose(echo((X|X) ,4,6) ,-5) ,7) ) ,-7) ,-7) ) ,4) +transpose(transpose(transpose(((X+transpose(X,12) ) |((X|X) |X) ) ,-5) ,4) ,7) ) ,4,6) ,12) ) ,12) ) ) ,7) ) ) +transpose((((echo(transpose((((transpose(echo((((arpeggio(X) +transpose(X,12) ) |(((X+X) +transpose((X|X) ,4) ) +transpose(X,7) ) ) +transpose(((X+transpose((X+transpose(X,7) ) ,12) ) +(X+transpose(transpose(X,-5) ,7) ) ) ,7) ) ,4,6) ,-5) +transpose((((step((X+transpose(transpose(shuffle(((X+transpose(X,4) ) +transpose(X,7) ) ) ,4) ,7) ) ,12) +transpose(transpose(transpose(transpose((((X+transpose(arpeggio(echo(X,4,6) ) ,4) ) +transpose(transpose(X,-5) ,7) ) +transpose((X+transpose(transpose(X,-7) ,7) ) ,12) ) ,4) ,-5) ,-5) ,4) ) +transpose(transpose(transpose(transpose(transpose((X+X) ,-5) ,-5) ,-7) ,-5) ,7) ) |arpeggio(transpose(transpose((X|X) ,4) ,-5) ) ) ,12) ) |shuffle(arpeggio(transpose(arpeggio(arpeggio(echo(X,4,6) ) ) ,-7) ) ) ) +transpose(shuffle((transpose(arpeggio(transpose((transpose(X,-7) +transpose(transpose(shuffle(X) ,-7) ,12) ) ,-7) ) ,-5) +transpose(transpose(echo(transpose(transpose((step(X,12) |X) ,-5) ,4) ,4,6) ,-5) ,12) ) ) ,12) ) ,-5) ,4,6) +transpose((arpeggio(shuffle((X+transpose((arpeggio(X) |((X+transpose(shuffle(X) ,4) ) +transpose(step(X,12) ,7) ) ) ,12) ) ) ) +transpose(transpose((transpose(transpose(transpose(transpose(((X|X) +transpose(echo(X,4,6) ,7) ) ,-5) ,4) ,4) ,-5) |transpose(((transpose(shuffle(((X|X) +transpose(X,12) ) ) ,4) |(arpeggio((arpeggio((X+X) ) +transpose(transpose(X,4) ,12) ) ) +transpose((X+transpose(X,4) ) ,12) ) ) |transpose((((transpose(X,-7) +transpose(X,4) ) +transpose(shuffle(X) ,7) ) +transpose(step(transpose(X,-7) ,12) ,7) ) ,-7) ) ,-7) ) ,-5) ,7) ) ,12) ) +transpose((transpose(((transpose((transpose(transpose(((transpose(X,-7) |transpose((transpose(X,4) +transpose(X,7) ) ,4) ) |transpose((transpose(transpose(X,-7) ,-7) +transpose(arpeggio(transpose(X,4) ) ,7) ) ,-5) ) ,-5) ,4) |transpose((((transpose(transpose((echo(shuffle(X) ,4,6) +transpose(X,12) ) ,4) ,4) +transpose((transpose((X|X) ,-5) |((echo(X,4,6) +transpose((X|X) ,7) ) |arpeggio((X+transpose(X,12) ) ) ) ) ,12) ) +(transpose(step(X,12) ,-5) |echo(transpose(X,4) ,4,6) ) ) |transpose(((((X+transpose(X,7) ) |((X+transpose(X,4) ) +transpose(X,7) ) ) +transpose(arpeggio(transpose(X,-7) ) ,7) ) |(arpeggio(X) |(echo(X,4,6) +transpose(echo(X,4,6) ,7) ) ) ) ,-7) ) ,-5) ) ,4) +transpose(transpose((arpeggio(transpose(transpose((step((transpose(transpose(X,4) ,-5) |transpose(X,4) ) ,12) +transpose(arpeggio((((X+transpose(X,4) ) +transpose(X,7) ) +(X|X) ) ) ,12) ) ,-5) ,-5) ) |transpose(arpeggio(((((transpose(step(X,12) ,4) |((X+transpose(X,7) ) |shuffle(transpose(X,4) ) ) ) |((shuffle(X) +transpose(((X|X) |X) ,4) ) +transpose(((X+transpose(X,12) ) +transpose(step(X,12) ,12) ) ,7) ) ) +transpose((X|shuffle(X) ) ,4) ) +transpose((transpose(step((X+transpose(X,7) ) ,12) ,4) +transpose((echo(transpose(X,-5) ,4,6) +transpose((((X|X) +transpose((X+transpose(X,7) ) ,7) ) +transpose(arpeggio(transpose(X,-7) ) ,7) ) ,12) ) ,12) ) ,7) ) ) ,4) ) ,-5) ,4) ) +transpose(shuffle(((((((transpose(transpose(arpeggio((X+transpose(X,12) ) ) ,-5) ,-5) +transpose((shuffle(step(X,12) ) |transpose(transpose(X,-7) ,-5) ) ,7) ) +(transpose(step(echo(X,4,6) ,12) ,-5) +transpose(echo((X+transpose(X,7) ) ,4,6) ,12) ) ) +transpose(((step(arpeggio(X) ,12) +transpose(((arpeggio(transpose(X,-7) ) +transpose(step((X|(X+transpose(X,7) ) ) ,12) ,4) ) +transpose(((transpose(X,-5) +transpose(arpeggio((X|X) ) ,4) ) +transpose(transpose(transpose(X,-5) ,-7) ,7) ) ,7) ) ,4) ) +transpose(step(((((X+transpose(X,12) ) |X) +transpose((X|X) ,12) ) +transpose((X+transpose((X+transpose(X,7) ) ,12) ) ,12) ) ,12) ,7) ) ,12) ) +(echo(transpose(echo((X|((X+transpose(X,12) ) +transpose(X,7) ) ) ,4,6) ,-7) ,4,6) +transpose(transpose(transpose(transpose(X,4) ,-5) ,-5) ,-5) ) ) +transpose(echo(echo((arpeggio(((transpose(X,4) +transpose(shuffle(X) ,4) ) +transpose(X,7) ) ) |(transpose(transpose((echo(((X+transpose(X,12) ) +X) ,4,6) +transpose((transpose(X,-5) +transpose(transpose(X,-5) ,7) ) ,12) ) ,-5) ,4) +(((transpose(echo((echo(X,4,6) |X) ,4,6) ,-7) +transpose(echo((transpose(X,4) |transpose((X+X) ,-5) ) ,4,6) ,4) ) +transpose(((arpeggio(transpose(X,-5) ) +transpose(shuffle(X) ,4) ) +transpose(transpose(X,-5) ,7) ) ,7) ) +step((transpose(X,4) +transpose(((X+transpose(X,7) ) |(((X+transpose(X,12) ) +transpose(shuffle(X) ,4) ) +transpose(X,7) ) ) ,12) ) ,12) ) ) ) ,4,6) ,4,6) ,4) ) +transpose(shuffle((transpose((((X+transpose(X,7) ) +transpose(((transpose(X,-7) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) ) +transpose(X,7) ) ,4) ) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) ,-7) |(((arpeggio(X) |step(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-5) ,12) ) |((((transpose(X,-5) +transpose((arpeggio(X) |X) ,4) ) +transpose(arpeggio(transpose(X,-5) ) ,7) ) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) ) +transpose(transpose(X,4) ,7) ) ) |transpose(transpose(X,4) ,-5) ) ) ) ,7) ) ) ,7) ) ,-7) +transpose(transpose(transpose(echo((step(transpose(transpose(shuffle((X+transpose(X,12) ) ) ,4) ,4) ,12) +transpose(((transpose(transpose(transpose(X,-7) ,4) ,4) +transpose((transpose(shuffle(transpose(transpose(X,-7) ,4) ) ,-7) +transpose(((((transpose(transpose(transpose(arpeggio(X) ,4) ,4) ,4) +transpose(((X|X) |X) ,4) ) +transpose(transpose(transpose(X,-7) ,-7) ,7) ) +transpose(transpose(transpose(((((X+transpose(X,12) ) +transpose(transpose(X,4) ,4) ) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) +transpose(arpeggio(transpose(X,-5) ) ,12) ) ,-7) ,-5) ,4) ) +transpose(transpose((arpeggio(X) +transpose(X,7) ) ,-5) ,7) ) ,12) ) ,4) ) +transpose(transpose((transpose(arpeggio(step(arpeggio(X) ,12) ) ,4) |((arpeggio((X+transpose(X,7) ) ) +transpose(transpose(transpose(transpose(X,4) ,-5) ,-5) ,4) ) +transpose(echo(X,4,6) ,7) ) ) ,4) ,7) ) ,12) ) ,4,6) ,4) ,4) ,12) ) ,7) ) +transpose((transpose((echo(transpose(transpose(transpose(transpose((X|X) ,-7) ,-7) ,-7) ,4) ,4,6) +((transpose((X+transpose(transpose(X,-7) ,7) ) ,4) +arpeggio((echo(transpose(X,-5) ,4,6) +transpose((transpose(X,-7) +transpose(X,12) ) ,12) ) ) ) +transpose(transpose(transpose(echo(X,4,6) ,-7) ,4) ,7) ) ) ,-5) |transpose(transpose(transpose((((transpose((X+transpose(X,7) ) ,-7) +transpose((X+X) ,4) ) +transpose(X,7) ) |(X+transpose(X,12) ) ) ,-5) ,4) ,-5) ) ,4) ) ,4) ) +transpose(transpose(((step(step(step(echo(((((transpose(X,-7) |(X+transpose(X,12) ) ) |((transpose(X,-7) +transpose(transpose(X,-5) ,4) ) +transpose(X,7) ) ) |transpose(transpose(transpose(X,4) ,-7) ,4) ) |transpose(step(echo(((X+transpose((X+transpose(X,12) ) ,4) ) +transpose(arpeggio(X) ,7) ) ,4,6) ,12) ,-5) ) ,4,6) ,12) ,12) ,12) |transpose((((transpose((((echo((transpose(X,-5) |X) ,4,6) +transpose(transpose((X+shuffle(X) ) ,4) ,7) ) +transpose((((((transpose((X+transpose(X,12) ) ,-5) +transpose(X,4) ) +transpose(step(X,12) ,7) ) +transpose(echo((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(X,-5) ) ,4,6) ,12) ) +transpose(transpose(X,-7) ,4) ) +transpose(step((shuffle(X) |transpose(X,4) ) ,12) ,7) ) ,12) ) +transpose(shuffle((echo(echo(shuffle(X) ,4,6) ,4,6) |transpose((arpeggio(X) +transpose(transpose(X,-5) ,7) ) ,-5) ) ) ,7) ) ,-7) |step((arpeggio(step(arpeggio(transpose(transpose(shuffle(transpose(X,-7) ) ,4) ,4) ) ,12) ) +shuffle((((X+transpose((X|X) ,12) ) |X) |transpose(step((X|X) ,12) ,4) ) ) ) ,12) ) +transpose(transpose((transpose(transpose(transpose(transpose(transpose((((X+X) +transpose(transpose((X|X) ,4) ,4) ) +transpose(arpeggio(X) ,7) ) ,-5) ,-7) ,4) ,-7) ,-5) +step(step(transpose(transpose((((transpose((step(transpose(X,-5) ,12) +transpose(transpose(transpose(X,-5) ,-5) ,7) ) ,4) +transpose((echo(step(X,12) ,4,6) +transpose(transpose((X|((X+transpose(X,4) ) +transpose(X,7) ) ) ,-5) ,12) ) ,4) ) +transpose(arpeggio(((X|X) +transpose(echo(X,4,6) ,12) ) ) ,7) ) +transpose((step(X,12) |X) ,12) ) ,-7) ,-5) ,12) ,12) ) ,-7) ,7) ) |(shuffle(step((((((X|X) +transpose((X+transpose(X,7) ) ,12) ) +transpose(step(transpose(X,4) ,12) ,4) ) +transpose((transpose(echo(transpose(X,4) ,4,6) ,-7) |((transpose(X,-5) +transpose(X,12) ) +transpose(X,7) ) ) ,7) ) +transpose((transpose(shuffle(transpose(X,-7) ) ,4) +transpose((step(X,12) |(X|X) ) ,7) ) ,12) ) ,12) ) |(echo(transpose(arpeggio(step(X,12) ) ,-5) ,4,6) |transpose(shuffle(transpose(shuffle((X|X) ) ,4) ) ,4) ) ) ) ,-7) ) |(echo(transpose(transpose(transpose(step(((((transpose(X,4) +transpose((transpose(X,-7) +transpose((X|X) ,12) ) ,7) ) |echo(((transpose(X,4) +transpose(X,4) ) +transpose((X|X) ,7) ) ,4,6) ) +transpose(transpose(((X+transpose(X,12) ) +transpose(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-5) ,7) ) ,-7) ,4) ) +transpose((transpose(X,-7) +transpose((X+X) ,12) ) ,7) ) ,12) ,-5) ,4) ,-5) ,4,6) +transpose((((shuffle(transpose((transpose(transpose(((X+transpose(X,12) ) |echo((X+transpose(X,7) ) ,4,6) ) ,4) ,-5) +transpose(echo(echo(transpose((transpose((X|X) ,4) +transpose(transpose((echo(X,4,6) +transpose(X,12) ) ,4) ,12) ) ,4) ,4,6) ,4,6) ,12) ) ,-7) ) |transpose(transpose((step((X+X) ,12) +transpose(X,12) ) ,4) ,-5) ) +transpose(echo(transpose(((((((transpose((step(X,12) |X) ,-5) +transpose(arpeggio(((step(X,12) +transpose(shuffle(X) ,4) ) +transpose(X,7) ) ) ,4) ) +transpose(transpose(transpose((X+transpose(X,12) ) ,4) ,4) ,7) ) |(((((X+X) +transpose(X,4) ) +transpose((X+transpose(X,12) ) ,7) ) +transpose(transpose(echo(transpose(X,-7) ,4,6) ,-7) ,4) ) +transpose(step(X,12) ,7) ) ) +transpose(transpose(((transpose(X,-7) +transpose(X,-7) ) |((X+transpose(X,12) ) +transpose(step(X,12) ,12) ) ) ,4) ,7) ) |step(echo(((echo(transpose(X,-5) ,4,6) +transpose(transpose(X,-5) ,7) ) +transpose((((X+transpose(X,4) ) +transpose(X,7) ) |X) ,12) ) ,4,6) ,12) ) |transpose(transpose(((shuffle(X) +transpose((X|X) ,4) ) +transpose(step(X,12) ,7) ) ,-7) ,4) ) ,-7) ,4,6) ,4) ) +transpose((transpose(echo(transpose(transpose((((((X+X) +transpose((X|transpose(X,4) ) ,7) ) +transpose(transpose(X,-5) ,4) ) +transpose(((arpeggio(X) +transpose(arpeggio(X) ,4) ) +transpose(((transpose(X,-7) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) ) +transpose(transpose(X,4) ,7) ) ,7) ) ,7) ) |((((X+transpose(X,7) ) |(X|X) ) +transpose(step(arpeggio(X) ,12) ,4) ) +transpose(echo(X,4,6) ,7) ) ) ,4) ,4) ,4,6) ,-5) |arpeggio(((shuffle(transpose(shuffle(X) ,-7) ) |((((((((transpose(X,4) |X) +transpose(arpeggio((X|X) ) ,4) ) +transpose((transpose(X,-7) +transpose(transpose(X,-5) ,12) ) ,7) ) +transpose(transpose(transpose(transpose((X+transpose(X,7) ) ,4) ,4) ,-7) ,4) ) +transpose(transpose(arpeggio(echo(X,4,6) ) ,-7) ,7) ) +transpose(shuffle(echo(X,4,6) ) ,4) ) +transpose(((((transpose(X,-5) |(X+X) ) +(X+transpose(X,12) ) ) +transpose(transpose((X+transpose(X,7) ) ,4) ,4) ) +transpose(transpose(transpose(shuffle(X) ,-5) ,4) ,7) ) ,7) ) +transpose(((transpose(transpose(X,4) ,4) |((X|X) +transpose(step(X,12) ,7) ) ) |(shuffle(step(transpose(X,4) ,12) ) |transpose(transpose(X,-7) ,-5) ) ) ,12) ) ) +transpose(transpose((shuffle((((X|X) +transpose((transpose(transpose(X,-7) ,4) +transpose(X,7) ) ,4) ) +transpose(step((step(transpose(X,-7) ,12) |(X+transpose((X+transpose(X,12) ) ,12) ) ) ,12) ,7) ) ) |(transpose(((transpose(X,4) +transpose(X,4) ) +transpose(shuffle(X) ,7) ) ,-7) |(((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(X,4) ) +transpose(X,7) ) |(transpose(X,-5) +transpose(arpeggio(X) ,7) ) ) ) ) ,-7) ,12) ) ) ) ,7) ) ,12) ) ) ,4) ,7) ) random seed used was 230842740

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