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(transpose((transpose(((((transpose(((shuffle(transpose(echo(transpose((X+X) ,-7) ,4,6) ,-5) ) +((echo(transpose(echo(X,4,6) ,-5) ,4,6) +echo((echo(X,4,6) +arpeggio(X) ) ,4,6) ) |echo((echo(X,4,6) +(X|(X|X) ) ) ,4,6) ) ) |transpose(step((transpose(echo(X,4,6) ,4) +echo(transpose(X,-7) ,4,6) ) ,12) ,-5) ) ,-5) +transpose(step((echo(((((transpose(X,4) +transpose(transpose(((X+X) |step(X,12) ) ,-7) ,4) ) +transpose((X|X) ,7) ) +(transpose(((X+X) |X) ,-7) +transpose((echo(X,4,6) +transpose(transpose(X,-5) ,12) ) ,7) ) ) +transpose(transpose((((X+transpose((X+X) ,7) ) +(shuffle(X) +transpose(X,12) ) ) +transpose(X,12) ) ,4) ,7) ) ,4,6) +transpose(transpose(step(((transpose((X+transpose(X,12) ) ,-7) |transpose(transpose(X,-5) ,-5) ) |transpose(echo(X,4,6) ,-5) ) ,12) ,-7) ,12) ) ,12) ,4) ) +transpose(((((transpose(transpose(transpose(transpose(X,-7) ,-7) ,-5) ,-7) +transpose((arpeggio(arpeggio((X|X) ) ) |(transpose(transpose(X,-5) ,-7) |(X+X) ) ) ,4) ) +transpose((((X|X) +transpose((transpose(X,4) +transpose(X,7) ) ,7) ) +transpose(arpeggio(((X+transpose(X,7) ) +transpose(transpose(transpose(X,4) ,4) ,7) ) ) ,12) ) ,7) ) |transpose((((echo(shuffle(transpose(X,4) ) ,4,6) +transpose(transpose(X,4) ,7) ) +transpose((transpose(((X+transpose(X,7) ) +((X+transpose(X,12) ) +transpose(echo(X,4,6) ,7) ) ) ,-5) +transpose(((X|((X+X) |X) ) |((transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-7) +transpose((X+X) ,4) ) +transpose(transpose(X,-5) ,7) ) ) ,7) ) ,4) ) +transpose(((arpeggio(shuffle(transpose(transpose(X,4) ,4) ) ) +transpose(((transpose(X,-7) +(((X+transpose(X,4) ) +transpose(X,7) ) +transpose(step(X,12) ,12) ) ) |step(transpose(echo(X,4,6) ,4) ,12) ) ,4) ) +transpose(transpose(((X+transpose(transpose((X+transpose(X,12) ) ,-7) ,4) ) +transpose(shuffle(arpeggio(transpose(X,-5) ) ) ,7) ) ,4) ,7) ) ,7) ) ,4) ) +transpose(shuffle(arpeggio((transpose(transpose(transpose(X,-7) ,4) ,-7) +(transpose(transpose((X+transpose(X,7) ) ,-5) ,-5) +transpose(transpose(transpose(X,-5) ,4) ,12) ) ) ) ) ,12) ) ,7) ) +transpose(shuffle(shuffle((step(transpose((step(X,12) +transpose((X|(X+X) ) ,12) ) ,4) ,12) +transpose(transpose(echo((transpose(X,-7) |((X|X) +transpose((X+transpose(X,12) ) ,12) ) ) ,4,6) ,-7) ,12) ) ) ) ,7) ) +((transpose(transpose((transpose(((shuffle(X) +step(X,12) ) +transpose((X+transpose(transpose(X,-5) ,7) ) ,-7) ) ,-5) +transpose(arpeggio(transpose((transpose(echo(X,4,6) ,-7) |transpose(transpose(transpose(X,4) ,-5) ,-7) ) ,-5) ) ,12) ) ,4) ,-5) +transpose(((transpose(((shuffle(transpose(echo(X,4,6) ,-5) ) +transpose(shuffle((X|transpose(X,-5) ) ) ,4) ) +transpose(((shuffle(step(X,12) ) +transpose((shuffle(X) +transpose(X,7) ) ,7) ) +(((X|X) |transpose(X,4) ) +transpose(((X+transpose(X,12) ) +arpeggio(shuffle(X) ) ) ,12) ) ) ,7) ) ,-5) +transpose((step(((X|X) +transpose(X,-5) ) ,12) +transpose(arpeggio(X) ,7) ) ,4) ) +transpose(((transpose(transpose(((((X+transpose(X,4) ) +transpose(X,7) ) +transpose((X+transpose(X,12) ) ,12) ) +transpose(((X+X) +((X+transpose(X,4) ) +transpose(X,7) ) ) ,12) ) ,4) ,-5) +transpose((transpose(((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(X,4) ) +transpose(transpose(X,-7) ,7) ) ,4) |step((X|X) ,12) ) ,12) ) +transpose((transpose(transpose(X,4) ,-7) |transpose((transpose(echo(X,4,6) ,-5) +transpose((transpose(X,-7) +transpose((X+X) ,12) ) ,7) ) ,4) ) ,7) ) ,7) ) ,4) ) +transpose(((((transpose(arpeggio((((X|X) |((X+transpose(X,4) ) +transpose(X,7) ) ) |((arpeggio(X) +transpose((X|X) ,12) ) |echo(transpose(X,-5) ,4,6) ) ) ) ,-7) +transpose((((shuffle((X|X) ) +transpose((X|X) ,4) ) +transpose((((X+transpose(X,4) ) +transpose(X,7) ) +transpose((X|X) ,12) ) ,7) ) +transpose(((X+transpose(X,12) ) |transpose(X,-5) ) ,-5) ) ,4) ) +((((transpose(((transpose(X,-5) +transpose(X,4) ) +transpose(transpose(X,-7) ,7) ) ,-7) +transpose((X+transpose((X|X) ,12) ) ,4) ) +transpose(((X+X) +transpose(((X|X) |((X+transpose(X,4) ) +transpose(X,7) ) ) ,7) ) ,7) ) +((X+transpose((X|X) ,7) ) +arpeggio(X) ) ) +transpose((transpose(X,-5) |((X+transpose(X,12) ) |(transpose(step(X,12) ,4) |transpose(transpose(X,-5) ,-5) ) ) ) ,12) ) ) +((((((transpose((X+transpose(X,12) ) ,-5) |((X|X) +transpose((X|X) ,7) ) ) +transpose((transpose(((X+transpose((X+X) ,7) ) |transpose(X,4) ) ,4) +transpose(transpose((transpose(X,-7) +X) ,4) ,7) ) ,4) ) +transpose(transpose(echo(arpeggio(transpose(X,-7) ) ,4,6) ,-5) ,7) ) +(transpose(echo((X+transpose(X,12) ) ,4,6) ,-7) +transpose(shuffle(transpose(X,-7) ) ,-7) ) ) +transpose((arpeggio(shuffle(echo(X,4,6) ) ) |(arpeggio(((X+transpose(X,7) ) +transpose(transpose(X,-5) ,7) ) ) +transpose(((transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-5) +transpose(((step(X,12) +transpose(transpose(X,4) ,4) ) +transpose(X,7) ) ,4) ) +transpose(transpose(X,-5) ,7) ) ,12) ) ) ,4) ) +transpose((transpose((echo(shuffle(X) ,4,6) +X) ,-7) +transpose((transpose(transpose(X,-5) ,-7) +transpose(arpeggio((X+transpose(X,12) ) ) ,12) ) ,12) ) ,7) ) ) +step(((transpose((transpose((X+transpose(X,12) ) ,4) +transpose(arpeggio(X) ,-7) ) ,4) |(transpose(transpose(X,-7) ,-5) +transpose((transpose(X,4) +echo(X,4,6) ) ,12) ) ) +transpose(((echo(((arpeggio(X) +transpose((X+X) ,4) ) +transpose(transpose(X,-7) ,7) ) ,4,6) +transpose(transpose(((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(arpeggio(X) ,4) ) +transpose((X|X) ,7) ) ,-5) ,7) ) +transpose((transpose(X,4) +transpose(transpose(X,4) ,12) ) ,-7) ) ,7) ) ,12) ) ,7) ) ) ,-7) |transpose((echo(transpose((((transpose(echo(((((X+transpose(X,12) ) +echo(X,4,6) ) +transpose(((arpeggio(X) +transpose((X+X) ,12) ) +transpose((X|transpose(X,-5) ) ,7) ) ,4) ) +transpose(transpose((X+transpose(X,7) ) ,-5) ,7) ) ,4,6) ,-7) +transpose(transpose(transpose((transpose(arpeggio(step(echo(arpeggio((X+transpose(X,12) ) ) ,4,6) ,12) ) ,-7) |(echo(((((X|X) +transpose((X+X) ,7) ) |transpose(arpeggio(X) ,4) ) +shuffle(transpose(step(X,12) ,-5) ) ) ,4,6) +transpose(arpeggio((X+transpose(X,7) ) ) ,7) ) ) ,-5) ,4) ,7) ) +transpose((transpose(transpose(transpose(transpose(transpose(shuffle(shuffle(X) ) ,4) ,-7) ,-7) ,-5) ,-5) +arpeggio(((((step(transpose((transpose(X,4) +transpose((transpose(X,-5) +transpose((X+transpose(X,12) ) ,12) ) ,12) ) ,-5) ,12) +transpose((transpose(X,-7) +transpose(X,7) ) ,-7) ) +transpose(((((X+transpose(X,4) ) +transpose((X+transpose((X|X) ,12) ) ,4) ) +transpose(X,7) ) +transpose((transpose(X,-7) +transpose((X+transpose(X,7) ) ,7) ) ,7) ) ,4) ) +transpose((transpose(X,-5) |shuffle(transpose(transpose(X,-7) ,-7) ) ) ,7) ) +(((transpose(transpose(transpose(X,-5) ,-5) ,-5) +(((X+X) +transpose((((transpose(X,-7) +transpose(X,4) ) +transpose((X|X) ,7) ) +transpose(((transpose(X,-5) +transpose(X,4) ) +transpose(X,7) ) ,12) ) ,7) ) +transpose(arpeggio(((X|(X+transpose(X,12) ) ) +transpose(echo((X+transpose(X,7) ) ,4,6) ,12) ) ) ,12) ) ) +transpose(transpose(arpeggio(X) ,-7) ,4) ) +transpose(transpose(transpose(arpeggio(X) ,4) ,4) ,7) ) ) ) ) ,4) ) +transpose(transpose((transpose(transpose((((X+X) |step(X,12) ) +transpose(((X+transpose(X,7) ) |X) ,7) ) ,-7) ,-5) |transpose(transpose(((transpose(X,-7) +transpose((X+X) ,4) ) +transpose(X,7) ) ,4) ,-7) ) ,-5) ,7) ) ,-5) ,4,6) +transpose((((X|(X+X) ) +transpose(((echo((X|X) ,4,6) +transpose((arpeggio(transpose(X,-5) ) |step(X,12) ) ,4) ) +transpose(((X+transpose((X+transpose(X,12) ) ,4) ) +transpose(transpose(X,-5) ,7) ) ,7) ) ,7) ) |(((transpose((((transpose(shuffle(transpose(X,4) ) ,-7) +transpose(transpose((X+transpose(X,7) ) ,4) ,12) ) +(transpose(transpose(((X+transpose(X,4) ) +transpose((X|X) ,7) ) ,-5) ,4) |(X|X) ) ) |((transpose(X,-7) +transpose(transpose(echo(X,4,6) ,-5) ,12) ) +transpose(((echo(X,4,6) +transpose((X|echo(X,4,6) ) ,12) ) +transpose(X,-5) ) ,4) ) ) ,-5) +shuffle(transpose(step(transpose(arpeggio(X) ,4) ,12) ,4) ) ) |(((arpeggio(((((X+transpose(X,4) ) +transpose(X,7) ) +step(X,12) ) +transpose(step(X,12) ,12) ) ) |((X+transpose(X,7) ) |((transpose((X+X) ,4) +transpose(step(transpose(X,4) ,12) ,4) ) +transpose(arpeggio(X) ,7) ) ) ) +transpose((step((step(X,12) |shuffle(X) ) ,12) |transpose(((((X+X) |X) |transpose(X,4) ) +((X+X) +X) ) ,-7) ) ,7) ) +transpose(((((echo((((X+X) |(X+transpose(X,7) ) ) |X) ,4,6) +transpose(echo(shuffle(echo(X,4,6) ) ,4,6) ,4) ) +transpose(shuffle((((X+transpose(transpose(X,-5) ,4) ) +transpose(step(X,12) ,7) ) |(((X+transpose(X,4) ) +transpose(X,7) ) |echo(X,4,6) ) ) ) ,7) ) +transpose(((transpose(((transpose(X,-7) |(X+transpose((X+transpose(X,7) ) ,7) ) ) |echo(echo(X,4,6) ,4,6) ) ,4) +transpose(((((transpose(X,4) |X) +transpose(transpose(transpose(X,-7) ,-7) ,4) ) +transpose(transpose(transpose(X,4) ,-5) ,7) ) +transpose((((transpose(X,-7) +transpose((X+transpose(X,7) ) ,7) ) +transpose(X,4) ) +transpose(((X+transpose(X,7) ) +transpose(X,4) ) ,7) ) ,12) ) ,4) ) +transpose(((transpose(X,4) +transpose(step((X+X) ,12) ,7) ) |shuffle(((X+transpose((X+transpose(X,12) ) ,7) ) +transpose(step(X,12) ,-7) ) ) ) ,7) ) ,12) ) |(transpose(X,-7) +transpose(transpose(X,4) ,-5) ) ) ,7) ) ) +transpose((transpose((transpose(((shuffle(X) +transpose(X,-7) ) +arpeggio(X) ) ,4) |(((((transpose(X,-5) +transpose(transpose((X+transpose(X,12) ) ,-5) ,4) ) +transpose(arpeggio(step(X,12) ) ,7) ) +transpose(step(transpose((X|X) ,-5) ,12) ,7) ) +transpose(transpose((X|X) ,4) ,-5) ) +(transpose(arpeggio((X|X) ) ,-7) |(arpeggio(transpose(X,-5) ) |(shuffle(arpeggio(X) ) +transpose(transpose(transpose(X,4) ,4) ,7) ) ) ) ) ) ,-7) +((shuffle(transpose((step(transpose(X,4) ,12) |(((X+transpose(X,4) ) +transpose(X,7) ) +(X|X) ) ) ,4) ) +transpose(transpose(shuffle(echo((transpose(X,4) +step(X,12) ) ,4,6) ) ,4) ,7) ) +transpose((transpose(((((shuffle(X) +transpose(echo(X,4,6) ,4) ) +transpose(step(X,12) ,7) ) +transpose((((transpose(X,4) +(X+transpose(X,7) ) ) +transpose(transpose(transpose(X,-7) ,4) ,4) ) +transpose(step((X+transpose(X,12) ) ,12) ,7) ) ,12) ) |(echo(transpose((X+transpose(X,12) ) ,-5) ,4,6) |transpose((X|X) ,-5) ) ) ,-5) |(echo(((shuffle((X+transpose(X,12) ) ) +transpose(X,12) ) +(X+echo(X,4,6) ) ) ,4,6) |transpose((shuffle(arpeggio(X) ) +(X+X) ) ,-5) ) ) ,7) ) ) ,-7) ) ) ,12) ) ,-7) ) ,-7) ,-7) +shuffle((step(transpose(transpose((step((transpose((X|transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-7) ) ,4) +transpose((transpose(X,-5) +(X+transpose((X|X) ,7) ) ) ,12) ) ,12) +transpose(transpose(((transpose(echo(X,4,6) ,-7) +transpose(echo(((X|X) +transpose(transpose(X,-5) ,7) ) ,4,6) ,4) ) +transpose(step(transpose(transpose(X,-7) ,-5) ,12) ,7) ) ,4) ,4) ) ,-5) ,4) ,12) +(arpeggio(arpeggio((((transpose(transpose(arpeggio(transpose(echo(transpose(X,-7) ,4,6) ,4) ) ,4) ,-7) +transpose((transpose(step(X,12) ,-5) +((arpeggio(step((X|X) ,12) ) +transpose(((((X+transpose(X,4) ) +transpose(X,7) ) +X) |echo(arpeggio(X) ,4,6) ) ,4) ) +transpose(((X+X) +transpose((X+X) ,4) ) ,7) ) ) ,4) ) +transpose(transpose((X+transpose((X+transpose(transpose(X,-5) ,12) ) ,12) ) ,-7) ,7) ) +transpose((transpose(transpose((X|arpeggio(X) ) ,-5) ,-5) |transpose((echo(step(X,12) ,4,6) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) ) ,-5) ) ,7) ) ) ) |((transpose(arpeggio(shuffle(((((echo((X+transpose(X,7) ) ,4,6) +transpose((((X+transpose(transpose(X,4) ,4) ) +transpose(transpose(X,-7) ,7) ) +((X+transpose(X,4) ) +transpose(X,7) ) ) ,12) ) +transpose((transpose((arpeggio(X) +transpose(X,12) ) ,4) +transpose(X,12) ) ,4) ) +transpose(transpose(shuffle(X) ,4) ,7) ) +transpose(((transpose(transpose(echo(X,4,6) ,4) ,4) +(transpose((X+X) ,-7) +X) ) +transpose(transpose(((((X+transpose(X,12) ) +transpose(X,12) ) |(echo(X,4,6) |step(X,12) ) ) +(transpose(X,-7) |(X+transpose(X,12) ) ) ) ,-7) ,12) ) ,12) ) ) ) ,4) +transpose(((transpose(step((X+transpose(X,7) ) ,12) ,-5) +arpeggio((step(((X|X) |step((X|X) ,12) ) ,12) +transpose(transpose(transpose(X,-5) ,-5) ,7) ) ) ) |transpose(transpose(echo(((transpose(((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(((X+transpose((((X|X) +transpose((X|X) ,4) ) +transpose(X,7) ) ,4) ) +transpose(transpose(X,4) ,7) ) ,7) ) +transpose(transpose(((X+transpose(X,4) ) +transpose(transpose(X,-7) ,7) ) ,-7) ,12) ) ,-5) +transpose(((transpose(shuffle((arpeggio(X) |X) ) ,-7) +transpose(transpose(((X+transpose(transpose((X|X) ,-7) ,7) ) +(transpose(X,-5) +(X|X) ) ) ,-7) ,4) ) +transpose((((arpeggio((X+X) ) +step(echo(step(X,12) ,4,6) ,12) ) +transpose(transpose((shuffle(X) +(X|X) ) ,4) ,4) ) +transpose(transpose(transpose((X+X) ,4) ,4) ,7) ) ,7) ) ,4) ) +transpose((transpose(transpose(X,-5) ,-7) +transpose(transpose((X+X) ,-5) ,-7) ) ,7) ) ,4,6) ,-5) ,4) ) ,4) ) +transpose(((((((transpose((transpose(transpose(X,4) ,-7) +transpose(X,7) ) ,-5) |arpeggio(transpose(step(step((X+transpose(X,12) ) ,12) ,12) ,-5) ) ) |shuffle(((X+transpose(X,12) ) +transpose(transpose(X,4) ,7) ) ) ) +transpose(transpose((transpose((X|X) ,4) +(transpose(X,4) +transpose((((X+X) +transpose(X,4) ) +transpose(transpose(X,-5) ,7) ) ,12) ) ) ,-5) ,12) ) +step((arpeggio(step(X,12) ) |transpose(transpose((transpose(X,-5) +transpose(X,7) ) ,-7) ,-7) ) ,12) ) +transpose(((((transpose(arpeggio(X) ,-7) +transpose((X+transpose(transpose(X,-7) ,7) ) ,4) ) +transpose((X|X) ,7) ) +transpose(((transpose((X+transpose(X,12) ) ,-7) +transpose(((X+transpose(X,7) ) |transpose(X,4) ) ,4) ) +transpose((X+transpose(transpose(X,4) ,7) ) ,7) ) ,4) ) +transpose(transpose(((transpose(X,-7) +transpose(transpose(X,-7) ,4) ) +transpose(arpeggio(X) ,7) ) ,-7) ,7) ) ,-5) ) +transpose(arpeggio(echo((((X+transpose((X|X) ,12) ) |((X+transpose(X,7) ) +step(X,12) ) ) |echo(echo(step(X,12) ,4,6) ,4,6) ) ,4,6) ) ,7) ) ,7) ) ) ) ) ) |transpose(((transpose(transpose(transpose(transpose(echo(transpose(shuffle(transpose((X+transpose(X,4) ) ,4) ) ,4) ,4,6) ,-7) ,-7) ,-5) ,4) +transpose(transpose(shuffle(((transpose(shuffle(step(echo(shuffle(transpose(transpose(X,4) ,-7) ) ,4,6) ,12) ) ,4) +shuffle((shuffle(((transpose((X+step(X,12) ) ,-5) +(((X+transpose(transpose(X,4) ,12) ) |X) |transpose(transpose(X,-5) ,4) ) ) +transpose(transpose(echo(transpose((X|X) ,4) ,4,6) ,-7) ,7) ) ) |(((step((step(((transpose(X,-5) +transpose(transpose(X,-7) ,4) ) +transpose((transpose(X,4) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,12) ) ,7) ) ,12) +transpose(transpose(X,4) ,7) ) ,12) +transpose(shuffle((transpose(((transpose((X+transpose((X+X) ,7) ) ,-7) +transpose(((X+X) |(step(X,12) +transpose(X,7) ) ) ,4) ) +transpose((X+transpose(transpose(transpose(X,4) ,-5) ,7) ) ,7) ) ,-7) |(echo(transpose(step(transpose(X,-7) ,12) ,-7) ,4,6) |(transpose(X,4) +X) ) ) ) ,4) ) +transpose(((((X+transpose(X,7) ) +transpose(shuffle(echo(X,4,6) ) ,12) ) |((arpeggio(shuffle(shuffle(X) ) ) +transpose(X,4) ) +transpose(((((shuffle(X) +transpose(echo(X,4,6) ,4) ) +transpose((X+X) ,7) ) +transpose(X,4) ) +transpose(transpose(X,4) ,7) ) ,7) ) ) +echo(transpose(((X+transpose(X,12) ) +transpose(step(X,12) ,7) ) ,4) ,4,6) ) ,7) ) +transpose(shuffle(shuffle(step(shuffle(shuffle(X) ) ,12) ) ) ,12) ) ) ) ) |step((((transpose(((step(X,12) |(X|X) ) +shuffle(X) ) ,-7) +transpose(transpose((X+transpose(X,7) ) ,-5) ,7) ) +transpose(transpose((X+transpose(transpose(X,4) ,12) ) ,4) ,12) ) +((transpose(X,-7) |transpose(((X|X) |X) ,4) ) |(shuffle(X) |transpose(transpose(((step(X,12) +transpose(echo(X,4,6) ,4) ) +transpose(X,7) ) ,-7) ,4) ) ) ) ,12) ) ) ,4) ,7) ) +transpose(((((echo(transpose(((shuffle(arpeggio(echo((X+X) ,4,6) ) ) |(arpeggio(transpose(X,4) ) +transpose((echo(((X+transpose((X|X) ,4) ) +transpose((X+transpose(X,12) ) ,7) ) ,4,6) +transpose((X+transpose((X+transpose(X,7) ) ,12) ) ,4) ) ,7) ) ) +transpose((transpose((X|X) ,4) +transpose((transpose(arpeggio(X) ,4) +transpose((transpose(X,4) +transpose(X,7) ) ,4) ) ,7) ) ,7) ) ,4) ,4,6) +echo(((transpose((echo(X,4,6) +transpose(step(shuffle(transpose(X,-7) ) ,12) ,12) ) ,4) |(transpose(transpose(X,-7) ,-5) +transpose(transpose(((X+transpose(shuffle(X) ,7) ) +transpose(((X+transpose((X|X) ,4) ) +transpose(X,7) ) ,12) ) ,-7) ,12) ) ) +transpose(arpeggio(echo(X,4,6) ) ,-7) ) ,4,6) ) +transpose(transpose(((transpose(transpose(((transpose(((((((X|X) +transpose((X|X) ,4) ) +transpose(transpose((step(X,12) +transpose(X,-5) ) ,4) ,7) ) +transpose(transpose(shuffle((X+transpose(X,12) ) ) ,4) ,12) ) +transpose(((transpose(((((X+X) +transpose(transpose(X,-7) ,4) ) +transpose(X,7) ) |transpose(transpose(X,4) ,4) ) ,4) +(transpose(X,4) +transpose((X+transpose(X,7) ) ,12) ) ) +(X+transpose(X,7) ) ) ,4) ) +transpose((transpose((transpose(((X+transpose(X,4) ) +transpose((X+X) ,7) ) ,4) +transpose((X|X) ,12) ) ,-7) +echo((transpose(step(((X+transpose(X,4) ) +transpose(X,7) ) ,12) ,-5) +transpose(step(transpose(shuffle(X) ,4) ,12) ,7) ) ,4,6) ) ,7) ) ,-5) +transpose(transpose((echo(X,4,6) |step(transpose((((X+transpose(X,4) ) +transpose(X,7) ) |(X|X) ) ,-5) ,12) ) ,-5) ,4) ) +transpose(transpose(transpose(transpose((transpose(X,-5) +transpose(step(X,12) ,12) ) ,4) ,4) ,4) ,7) ) ,4) ,-5) +transpose(((transpose(((transpose((transpose(X,-5) +transpose(transpose(X,-5) ,7) ) ,-7) |(transpose(transpose((X|X) ,4) ,-5) |((transpose((arpeggio(shuffle(X) ) +(echo(X,4,6) +transpose(transpose(X,4) ,7) ) ) ,-5) +transpose(transpose((X+transpose((X+X) ,-7) ) ,4) ,4) ) +transpose(transpose((arpeggio(X) +(X+X) ) ,4) ,7) ) ) ) +transpose((((arpeggio(transpose((X|X) ,-7) ) +transpose(transpose((echo(X,4,6) +transpose(X,12) ) ,-7) ,-5) ) +transpose(arpeggio((X+(transpose(X,-5) +transpose(transpose(X,-5) ,12) ) ) ) ,12) ) +transpose((transpose(transpose(X,-7) ,4) +transpose((X+X) ,12) ) ,7) ) ,7) ) ,-7) +transpose(shuffle(transpose((arpeggio(shuffle((transpose((X|X) ,-7) +transpose(transpose(transpose(X,-7) ,4) ,12) ) ) ) |transpose(X,4) ) ,-5) ) ,4) ) +transpose((step(echo(transpose(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-7) ,-7) ,4,6) ,12) +transpose(step(((shuffle((X+X) ) +transpose((((X+X) +transpose(arpeggio(X) ,4) ) +transpose(echo((X|X) ,4,6) ,7) ) ,4) ) +transpose((X+X) ,7) ) ,12) ,7) ) ,7) ) ,4) ) +transpose((transpose(transpose(transpose(((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(X,-5) ) +step(shuffle((X+transpose(X,7) ) ) ,12) ) ,-5) ,-7) ,-5) +(echo(shuffle(transpose(arpeggio((X|X) ) ,4) ) ,4,6) +transpose((step(transpose(transpose(X,-7) ,-7) ,12) +transpose((arpeggio((((arpeggio(X) +transpose((X+X) ,7) ) +transpose(transpose(X,-5) ,4) ) +transpose((X+transpose(X,7) ) ,7) ) ) |(((X+transpose(arpeggio(X) ,4) ) +transpose((X+transpose(X,12) ) ,7) ) +transpose(echo(transpose(X,4) ,4,6) ,7) ) ) ,12) ) ,12) ) ) ,7) ) ,-5) ,7) ) +transpose(arpeggio(arpeggio(transpose(shuffle(X) ,-7) ) ) ,-5) ) +transpose((transpose((((((transpose(arpeggio(transpose(transpose(transpose((X+transpose(X,12) ) ,-5) ,-7) ,4) ) ,-5) +transpose(transpose(transpose(transpose(transpose((X+X) ,-5) ,4) ,4) ,-7) ,-7) ) +((transpose(transpose(transpose((transpose(X,4) |arpeggio((transpose(X,-5) +transpose(X,-5) ) ) ) ,-7) ,-7) ,-7) +transpose((((transpose((transpose(X,-7) +echo(X,4,6) ) ,4) +transpose(echo((X+transpose((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(step((X+transpose(X,12) ) ,12) ,7) ) ,12) ) ,4,6) ,4) ) +transpose(step((echo(X,4,6) +transpose(transpose(X,-5) ,12) ) ,12) ,7) ) +step(shuffle(arpeggio((X+X) ) ) ,12) ) ,7) ) +transpose(transpose((((transpose(((X+transpose((X|X) ,4) ) +transpose(transpose(X,-7) ,7) ) ,-5) +transpose((((X+X) +transpose((X|X) ,7) ) |arpeggio(X) ) ,4) ) +transpose(((step(X,12) +transpose(transpose(transpose(X,4) ,4) ,4) ) +transpose(X,7) ) ,7) ) +(echo(X,4,6) +((transpose(X,-7) +transpose((transpose(X,4) +transpose((X+transpose(X,12) ) ,12) ) ,4) ) +transpose(transpose(transpose((X+transpose(X,7) ) ,4) ,4) ,7) ) ) ) ,4) ,12) ) ) +arpeggio(((transpose(echo(echo((transpose(X,4) |transpose(X,4) ) ,4,6) ,4,6) ,-7) +transpose(echo((echo((((X+transpose(X,12) ) +transpose(transpose(X,4) ,4) ) +transpose(X,7) ) ,4,6) +(((X|transpose(X,-7) ) +transpose((X|X) ,12) ) +transpose(X,4) ) ) ,4,6) ,4) ) +transpose(arpeggio(((echo(((transpose(X,-7) +transpose(step(X,12) ,7) ) |X) ,4,6) +transpose(transpose(((X+transpose(X,7) ) +(X+(X|X) ) ) ,4) ,4) ) +transpose(transpose(echo(transpose(echo(X,4,6) ,-7) ,4,6) ,-7) ,7) ) ) ,7) ) ) ) +transpose(transpose(transpose((transpose((echo(transpose(transpose(transpose(X,-5) ,-7) ,-7) ,4,6) +arpeggio((X+(X|X) ) ) ) ,4) +shuffle(((((transpose(shuffle((X|X) ) ,4) +transpose(transpose(X,-5) ,4) ) +transpose(transpose(echo(transpose(X,-5) ,4,6) ,-7) ,7) ) |echo((((X+((X+transpose(X,12) ) |X) ) +transpose(((X+transpose(X,12) ) +arpeggio(X) ) ,4) ) +transpose(((X+transpose(X,7) ) +transpose(step(X,12) ,7) ) ,7) ) ,4,6) ) +(echo(X,4,6) |echo(echo(X,4,6) ,4,6) ) ) ) ) ,-5) ,-5) ,4) ) +transpose((((((step(echo((transpose(transpose(transpose(X,4) ,-7) ,-7) +transpose(((arpeggio(X) |(X+transpose(arpeggio(X) ,12) ) ) +step(transpose(X,-5) ,12) ) ,4) ) ,4,6) ,12) +transpose((transpose((transpose((echo((transpose(X,4) |(X+X) ) ,4,6) |transpose(transpose(X,-5) ,4) ) ,-7) +transpose(((transpose(X,4) +X) +shuffle((echo(X,4,6) +transpose(transpose(X,-5) ,7) ) ) ) ,12) ) ,4) +transpose(((((((step(X,12) +X) +transpose(X,-7) ) +transpose(((arpeggio((X|(X+transpose(X,7) ) ) ) +transpose((transpose(transpose(X,4) ,-7) +transpose(X,-5) ) ,4) ) +transpose(transpose(((X+transpose(X,7) ) +transpose((X|X) ,7) ) ,4) ,7) ) ,4) ) +transpose((((X|X) +transpose(transpose(X,-5) ,4) ) +transpose((X|transpose(X,-7) ) ,7) ) ,7) ) +transpose((((step(X,12) +transpose(transpose(X,4) ,4) ) +transpose(shuffle(X) ,7) ) +echo(step(transpose(X,4) ,12) ,4,6) ) ,-5) ) |(transpose((X|(X+X) ) ,-5) +((shuffle(X) |arpeggio(X) ) +transpose(transpose(shuffle((X|X) ) ,4) ,7) ) ) ) ,7) ) ,12) ) +transpose(transpose(arpeggio(((transpose((transpose(X,4) |(X+transpose(X,7) ) ) ,-7) +(transpose(X,-7) |transpose(X,-5) ) ) +transpose(transpose(transpose((((((X+transpose(X,4) ) +transpose(X,7) ) |(X+transpose(X,12) ) ) |arpeggio((X+transpose(X,12) ) ) ) |echo((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(X,7) ) ,4,6) ) ,-5) ,-5) ,12) ) ) ,-7) ,4) ) +transpose((echo(transpose(shuffle((X+transpose((X+X) ,7) ) ) ,4) ,4,6) +transpose(transpose(((transpose(((((transpose(X,-7) |((X+transpose(X,7) ) +step(X,12) ) ) +transpose(shuffle((X|(X|X) ) ) ,4) ) +transpose((transpose(echo(X,4,6) ,4) +((transpose(X,-7) +transpose(X,4) ) +transpose(X,7) ) ) ,7) ) |transpose(transpose(echo(X,4,6) ,4) ,4) ) ,4) +transpose(((((((X+transpose(arpeggio(X) ,4) ) +transpose(X,7) ) +transpose(X,7) ) +step((echo(X,4,6) +transpose((X+X) ,7) ) ,12) ) +transpose((((transpose(arpeggio(X) ,4) +transpose(echo(arpeggio(X) ,4,6) ,12) ) +transpose(transpose(transpose(transpose(X,4) ,4) ,4) ,4) ) +transpose((echo(echo(X,4,6) ,4,6) |X) ,7) ) ,4) ) +transpose(transpose(X,4) ,7) ) ,4) ) +transpose(transpose(echo(transpose((X+X) ,4) ,4,6) ,-5) ,7) ) ,4) ,12) ) ,7) ) +transpose(shuffle(arpeggio(((transpose((((transpose(transpose(X,4) ,-7) +transpose(shuffle(arpeggio((X+transpose(X,-7) ) ) ) ,4) ) +transpose(transpose(transpose((X+X) ,4) ,-5) ,7) ) +transpose(step((arpeggio((step(X,12) +transpose(X,12) ) ) |echo(transpose(X,4) ,4,6) ) ,12) ,7) ) ,4) +transpose(((((X+X) +transpose(echo((X|X) ,4,6) ,7) ) +transpose(transpose(shuffle(transpose(X,-5) ) ,-7) ,7) ) +transpose((transpose((transpose(transpose((X+X) ,-5) ,-5) |(((((X+((X+transpose(X,4) ) +transpose(X,7) ) ) +transpose(step(X,12) ,4) ) +transpose((X+X) ,7) ) +transpose(shuffle(transpose((X|X) ,4) ) ,4) ) +transpose(((X+transpose(arpeggio(X) ,4) ) +transpose(shuffle(X) ,7) ) ,7) ) ) ,4) +transpose((((transpose(X,-5) +(X+X) ) +transpose(transpose(shuffle((X+transpose(X,7) ) ) ,-7) ,4) ) +transpose((X+(X+X) ) ,7) ) ,12) ) ,7) ) ,4) ) +transpose(((transpose(X,4) +transpose(X,4) ) +transpose(shuffle(transpose((shuffle(X) |((arpeggio(shuffle(X) ) +transpose(step(X,12) ,4) ) +transpose((X+transpose(step(X,12) ,12) ) ,7) ) ) ,-5) ) ,12) ) ,7) ) ) ) ,4) ) +transpose((echo((transpose(((shuffle(shuffle((X|X) ) ) +transpose(transpose(X,4) ,4) ) +transpose(transpose(X,4) ,7) ) ,4) +transpose(echo(transpose(step(transpose(transpose(X,-7) ,-5) ,12) ,4) ,4,6) ,12) ) ,4,6) |shuffle(arpeggio(((arpeggio(transpose((X+transpose((X+X) ,7) ) ,4) ) +transpose(((((((X+transpose(X,12) ) |X) +transpose(transpose(echo(X,4,6) ,-7) ,4) ) +transpose(step(X,12) ,7) ) +transpose(transpose(step(X,12) ,-5) ,4) ) +transpose((shuffle(X) +transpose(transpose(X,-5) ,12) ) ,7) ) ,4) ) +transpose(transpose((((transpose(X,4) +transpose((transpose(X,-5) |X) ,4) ) +transpose((transpose(X,4) +transpose(shuffle(X) ,7) ) ,7) ) +((X|X) +transpose(transpose(X,4) ,7) ) ) ,-5) ,7) ) ) ) ) ,7) ) ,7) ) ,4) +transpose((((transpose((((((((X+transpose(echo(X,4,6) ,12) ) |step(transpose(X,-7) ,12) ) +echo(transpose(X,-7) ,4,6) ) +transpose(transpose(transpose(transpose(X,-5) ,-5) ,-7) ,4) ) +transpose((step(transpose((X+X) ,4) ,12) +(X+transpose(echo(X,4,6) ,12) ) ) ,7) ) +transpose(transpose(echo(transpose(transpose(transpose(X,-7) ,4) ,-5) ,4,6) ,-7) ,12) ) +transpose(((echo(arpeggio(X) ,4,6) |(echo(transpose((X+transpose(X,7) ) ,4) ,4,6) +transpose(step(transpose((X|X) ,-5) ,12) ,12) ) ) +echo(transpose((transpose(X,-5) |X) ,-7) ,4,6) ) ,-5) ) ,4) +transpose(shuffle(transpose(step((shuffle(((X+transpose(X,4) ) +transpose(X,7) ) ) +transpose(transpose((X+transpose(X,7) ) ,-7) ,7) ) ,12) ,4) ) ,12) ) +shuffle(((transpose(((X|X) |((((shuffle(X) |X) +transpose(step((X+X) ,12) ,12) ) +transpose(((X+transpose(step(X,12) ,4) ) +transpose((X+X) ,7) ) ,7) ) |transpose(transpose(X,-5) ,-5) ) ) ,-5) +(transpose((transpose(X,4) +transpose((X|(transpose(X,-5) +transpose(X,-7) ) ) ,7) ) ,4) +transpose(transpose(((X+transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) ) +transpose((X|transpose(X,-5) ) ,7) ) ,4) ,7) ) ) +transpose(echo((echo(transpose(transpose(X,4) ,4) ,4,6) +transpose(((shuffle(transpose(X,-7) ) +transpose((transpose(echo(X,4,6) ,-5) |arpeggio((X+X) ) ) ,4) ) +transpose(transpose((transpose(X,-5) +transpose(X,12) ) ,4) ,7) ) ,12) ) ,4,6) ,-5) ) ) ) +transpose(transpose(arpeggio(step(echo((transpose(((shuffle(transpose(X,-7) ) |transpose(X,4) ) +transpose(step((transpose(X,4) +transpose(X,12) ) ,12) ,12) ) ,4) |(transpose(transpose(X,4) ,4) |(((shuffle(X) +transpose(echo(X,4,6) ,4) ) +transpose((X|X) ,7) ) +X) ) ) ,4,6) ,12) ) ,4) ,12) ) ,7) ) ,7) ) ,-5) ) ,-7) ) random seed used was 241209255

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