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:
Phrase for X:
# of Tracks:
Randomize patches:
 

Results may not appear for a few seconds.
Be patient!
Do you like this result? Do you want to let other people listen to it?

Save this one in the
Tune Trove!

See what's already
in the Tune Trove!

After 20 generations the expression "X" became this:
(transpose(shuffle((transpose(transpose((((((((arpeggio(shuffle(transpose(shuffle(arpeggio((X+transpose(X,7) ) ) ) ,-5) ) ) +transpose(arpeggio((shuffle(((X|X) +transpose((X+transpose(X,7) ) ,7) ) ) +transpose(transpose(transpose((X+transpose(X,12) ) ,-5) ,-7) ,7) ) ) ,12) ) +transpose(transpose((((((X|X) +transpose(transpose(X,4) ,4) ) +transpose((transpose(X,-5) +(X+X) ) ,7) ) +transpose(transpose(step(transpose(X,-5) ,12) ,-5) ,4) ) +transpose(((X+transpose(transpose(X,4) ,12) ) |step((X+transpose(X,7) ) ,12) ) ,7) ) ,-7) ,4) ) +transpose(transpose((X+step((X+transpose(X,7) ) ,12) ) ,-5) ,7) ) +((transpose(echo(X,4,6) ,-7) +transpose(((((arpeggio((X+transpose(X,12) ) ) +X) +(X|X) ) +transpose(transpose(transpose(X,-7) ,-7) ,4) ) +transpose(((transpose(((X+transpose(arpeggio(X) ,4) ) +transpose(echo(X,4,6) ,7) ) ,4) +transpose(transpose((X+transpose(X,12) ) ,4) ,4) ) +transpose(transpose((X+X) ,4) ,7) ) ,7) ) ,12) ) +transpose(((transpose(shuffle(transpose((transpose(transpose(X,-7) ,4) |arpeggio(transpose(X,-7) ) ) ,4) ) ,4) +transpose((((((X+X) +transpose(transpose(transpose(X,-7) ,-7) ,-7) ) +transpose(((X|((X+transpose(X,4) ) +transpose(X,7) ) ) |(transpose(X,-5) +transpose(step(((X+transpose(X,4) ) +transpose(X,7) ) ,12) ,12) ) ) ,4) ) +transpose(arpeggio((((X+transpose(X,4) ) +transpose(X,7) ) |X) ) ,7) ) +(transpose(echo(X,4,6) ,4) |transpose(shuffle(transpose(X,-5) ) ,-5) ) ) ,4) ) +transpose(((step(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) ,12) +transpose(shuffle(transpose((X+transpose(X,12) ) ,-5) ) ,12) ) |((X+transpose(X,4) ) +transpose(X,7) ) ) ,7) ) ,12) ) ) |echo(arpeggio(shuffle(transpose((transpose((X+X) ,-7) +transpose((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(transpose(X,4) ,7) ) ,-5) ) ,-7) ) ) ,4,6) ) |((echo((transpose(transpose(((X+transpose(X,12) ) |X) ,-5) ,-5) +transpose(((echo(X,4,6) +(X+X) ) +transpose(transpose((X+(X+transpose(X,7) ) ) ,-7) ,-5) ) ,7) ) ,4,6) +transpose(echo((transpose((X|transpose(X,-5) ) ,4) +transpose((arpeggio(transpose((arpeggio(X) +transpose((X|X) ,12) ) ,-5) ) +((step(X,12) +transpose(step(step((X+transpose(X,12) ) ,12) ,12) ,4) ) +transpose(arpeggio((X+transpose(transpose(X,-5) ,7) ) ) ,7) ) ) ,12) ) ,4,6) ,12) ) +transpose(transpose(((((echo((arpeggio(X) +X) ,4,6) |((X+X) +X) ) +transpose((((X+transpose(X,4) ) +transpose(X,7) ) |transpose(X,-5) ) ,7) ) |(((echo(((X+transpose(X,4) ) +transpose(X,7) ) ,4,6) +transpose(transpose((X+X) ,-5) ,7) ) +(X|(X|X) ) ) +shuffle((step(X,12) |transpose(step(transpose(X,4) ,12) ,-5) ) ) ) ) +transpose(arpeggio(arpeggio(((((arpeggio(X) +transpose(transpose(X,-5) ,4) ) +transpose(echo(transpose(X,-7) ,4,6) ,7) ) +transpose((X+transpose(X,7) ) ,12) ) +transpose((X|(X+X) ) ,12) ) ) ) ,12) ) ,4) ,7) ) ) +transpose(arpeggio(arpeggio(arpeggio(((X+transpose(echo(X,4,6) ,7) ) +transpose(transpose(X,-5) ,4) ) ) ) ) ,12) ) ,-5) ,4) |step((((transpose(shuffle(transpose(transpose(step(transpose(X,-7) ,12) ,4) ,-7) ) ,-7) +(((echo((X+transpose(X,12) ) ,4,6) |transpose((((X+transpose(X,12) ) +transpose(X,4) ) +transpose((X|X) ,7) ) ,-7) ) +(transpose(transpose(echo(transpose(transpose((X+X) ,-5) ,-5) ,4,6) ,-5) ,-7) +transpose(transpose((((X+transpose(X,12) ) |transpose(X,-5) ) +((shuffle((X+X) ) +arpeggio(X) ) +transpose(step(X,12) ,7) ) ) ,-7) ,7) ) ) +transpose(transpose((transpose(transpose((X+X) ,4) ,4) +((transpose(X,4) +echo(X,4,6) ) +shuffle((X+X) ) ) ) ,-5) ,-7) ) ) +transpose(((((((transpose(((X+transpose(X,7) ) +transpose(step(transpose(X,4) ,12) ,12) ) ,-7) +transpose(transpose(X,4) ,12) ) +transpose(((((shuffle((X+transpose(X,7) ) ) +transpose(transpose(transpose(transpose(X,-7) ,-5) ,4) ,4) ) +transpose((step((X+X) ,12) +transpose(step(X,12) ,12) ) ,7) ) |shuffle((X|X) ) ) |(arpeggio(X) +transpose(step(X,12) ,-7) ) ) ,4) ) +transpose(arpeggio(shuffle((X+X) ) ) ,7) ) +transpose(echo((((transpose(((transpose(X,-7) |(X+transpose(X,12) ) ) +transpose(((((X+X) +transpose(X,4) ) +transpose((X|X) ,7) ) +transpose(((transpose(X,-7) +transpose(X,4) ) +transpose(transpose(X,4) ,7) ) ,12) ) ,12) ) ,-5) +transpose(transpose(transpose(X,4) ,4) ,12) ) +transpose(transpose(((X|transpose(X,4) ) +transpose(transpose(((transpose(X,4) +transpose((X+transpose(X,7) ) ,4) ) +transpose(X,7) ) ,-5) ,7) ) ,-7) ,4) ) +transpose(arpeggio(step((step(X,12) +arpeggio(X) ) ,12) ) ,7) ) ,4,6) ,4) ) +transpose(transpose((((echo(arpeggio(transpose(X,4) ) ,4,6) +transpose(transpose((arpeggio((X+transpose(X,12) ) ) +transpose(X,7) ) ,-5) ,7) ) +((shuffle(X) +transpose((((echo(X,4,6) +transpose((arpeggio((X+X) ) |transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-7) ) ,4) ) +transpose(transpose(echo(arpeggio(X) ,4,6) ,-5) ,7) ) +(transpose((X+X) ,-5) +transpose(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) ,7) ) ) ,4) ) +transpose(transpose(transpose(step(arpeggio(X) ,12) ,-7) ,-5) ,7) ) ) +transpose(transpose(transpose((transpose(X,-5) +arpeggio(echo(X,4,6) ) ) ,4) ,4) ,12) ) ,4) ,7) ) |echo(transpose(shuffle(step((((arpeggio(X) |((X+transpose(X,7) ) +transpose(X,4) ) ) +echo(X,4,6) ) +transpose(transpose(echo(transpose(X,-5) ,4,6) ,-5) ,12) ) ,12) ) ,-5) ,4,6) ) ,4) ) +transpose(((step(((transpose(((((X+transpose(X,12) ) +(X+transpose(X,7) ) ) +transpose(transpose(X,4) ,4) ) +transpose((transpose(X,4) +X) ,7) ) ,-7) +transpose(transpose(((X+X) +(X|X) ) ,-5) ,12) ) +transpose(((((((X+transpose(X,-7) ) +transpose(transpose((X+X) ,-7) ,4) ) +transpose(transpose(X,-7) ,7) ) +transpose(transpose(((X+X) +transpose((X+transpose(X,12) ) ,12) ) ,-5) ,4) ) +transpose(arpeggio(transpose(X,-5) ) ,7) ) +transpose(shuffle((transpose(X,4) +((X+transpose((X+transpose(X,7) ) ,4) ) +transpose((X+transpose(X,12) ) ,7) ) ) ) ,12) ) ,4) ) ,12) |transpose((((X+X) |transpose(step(X,12) ,-7) ) +transpose(shuffle(((transpose(X,-5) +transpose(X,4) ) +transpose((X+transpose(X,7) ) ,7) ) ) ,4) ) ,4) ) +(transpose(((((transpose((transpose(step(X,12) ,-5) +transpose(transpose(arpeggio(X) ,4) ,4) ) ,4) +transpose(transpose(transpose((((X+transpose(X,12) ) +transpose(shuffle((X+X) ) ,7) ) +transpose((transpose(X,-7) +transpose(X,-7) ) ,12) ) ,4) ,4) ,4) ) +transpose((((transpose(X,-5) |step(transpose(X,-5) ,12) ) +transpose(echo(transpose((X+(X+X) ) ,-5) ,4,6) ,7) ) +transpose(transpose(transpose((((transpose(X,-5) +transpose(X,7) ) +transpose(transpose(transpose(X,-5) ,-7) ,4) ) +transpose(transpose((X|X) ,-5) ,7) ) ,-5) ,4) ,12) ) ,7) ) +transpose(echo(transpose((transpose(X,-7) +transpose((X|X) ,12) ) ,4) ,4,6) ,7) ) |(((transpose((echo(X,4,6) +transpose(transpose((X|step(X,12) ) ,-7) ,7) ) ,4) +(shuffle(transpose(X,4) ) |(transpose(X,-5) +(X|(X|X) ) ) ) ) |(((echo(X,4,6) +X) |(X|X) ) +(shuffle(X) +transpose((X+transpose(X,7) ) ,7) ) ) ) +((transpose(((transpose(transpose((((X+transpose(X,12) ) +transpose(X,4) ) +transpose(X,7) ) ,-5) ,-5) +transpose(transpose(transpose(X,4) ,-7) ,4) ) +transpose(shuffle(step(((X+transpose(X,4) ) +transpose(X,7) ) ,12) ) ,7) ) ,4) +transpose(((transpose(X,4) +transpose(transpose(X,-5) ,4) ) +transpose(((transpose(transpose(((X+transpose(X,7) ) +transpose(X,7) ) ,-7) ,-7) +transpose((transpose((transpose(X,4) +shuffle(X) ) ,4) |(transpose(X,4) +transpose(transpose((X+X) ,4) ,7) ) ) ,4) ) +transpose(transpose(X,-7) ,7) ) ,7) ) ,4) ) +transpose((transpose(echo(((X|X) +(X+transpose(X,7) ) ) ,4,6) ,-7) +transpose(arpeggio(((((X+transpose(X,12) ) +transpose(X,-7) ) +transpose((transpose(X,4) |X) ,4) ) +transpose((transpose(X,-5) +(X+transpose(X,7) ) ) ,7) ) ) ,12) ) ,7) ) ) ) ,-5) +(shuffle(transpose(transpose(((shuffle(X) +echo(X,4,6) ) |transpose(X,4) ) ,4) ,-5) ) +transpose(transpose(((transpose((transpose(X,4) +transpose(X,7) ) ,4) |shuffle(transpose(arpeggio(X) ,-7) ) ) |shuffle(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-7) ) ) ,-5) ,7) ) ) ) ,7) ) ,12) ) ) ,-7) +transpose(transpose((transpose(((transpose((((step(X,12) +transpose(step(X,12) ,7) ) +X) +step(transpose((X+transpose(X,7) ) ,-5) ,12) ) ,-5) +transpose(transpose((echo(X,4,6) |X) ,4) ,12) ) +transpose(((transpose(X,-5) +transpose(transpose(X,4) ,12) ) +transpose(echo(step(((X|X) |transpose(X,-5) ) ,12) ,4,6) ,12) ) ,12) ) ,4) +transpose((((step(arpeggio((X+transpose(arpeggio(step(X,12) ) ,12) ) ) ,12) +transpose(transpose(echo(arpeggio(X) ,4,6) ,-7) ,-7) ) +transpose(shuffle(echo(transpose((transpose(echo(arpeggio(transpose(X,4) ) ,4,6) ,-7) +transpose(arpeggio(X) ,7) ) ,4) ,4,6) ) ,7) ) +transpose(transpose(arpeggio(((arpeggio((((X+transpose(X,7) ) |transpose(X,-7) ) +(transpose(X,4) +(X|X) ) ) ) +(((echo(step(X,12) ,4,6) +transpose(transpose(transpose(X,-5) ,-5) ,12) ) +(transpose(X,-5) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,12) ) ) +transpose(arpeggio(X) ,12) ) ) +transpose(((arpeggio((X+transpose(X,12) ) ) +transpose(arpeggio(((X+transpose(X,7) ) +arpeggio(X) ) ) ,4) ) +transpose((X|(X+X) ) ,7) ) ,7) ) ) ,-5) ,7) ) ,7) ) ,-5) ,-5) )
random seed used was 16323826

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