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(transpose(transpose(((transpose((((arpeggio((X+transpose(X,7) ) ) +arpeggio(transpose((transpose(transpose(X,-7) ,-5) +((X+transpose(X,4) ) +transpose(X,7) ) ) ,-5) ) ) +transpose(transpose((transpose(step((X|X) ,12) ,4) |(X+((X+transpose(X,4) ) +transpose(X,7) ) ) ) ,4) ,4) ) +transpose(transpose(echo(X,4,6) ,4) ,7) ) ,-5) +transpose(step((((transpose(echo(X,4,6) ,4) +echo(X,4,6) ) +((X+X) +transpose(arpeggio(transpose(X,-7) ) ,7) ) ) +transpose(transpose(step((X|X) ,12) ,4) ,12) ) ,12) ,7) ) +(transpose(step(transpose(arpeggio(transpose(X,4) ) ,4) ,12) ,-7) |transpose(transpose((arpeggio(transpose(transpose(X,-5) ,-5) ) |transpose((transpose(transpose(X,4) ,4) +transpose((X+transpose(X,12) ) ,12) ) ,-5) ) ,-5) ,4) ) ) ,-7) ,-7) ,-5) +step(shuffle(((transpose(arpeggio((shuffle((transpose(arpeggio((((shuffle((X+X) ) +transpose((((transpose(X,-5) |X) +transpose((X+arpeggio(X) ) ,4) ) +transpose((arpeggio(X) +transpose(X,-5) ) ,7) ) ,4) ) +transpose(arpeggio(X) ,7) ) +((transpose(step(X,12) ,-5) +transpose(arpeggio(transpose(X,-7) ) ,12) ) |shuffle(transpose(X,-7) ) ) ) ) ,-5) +transpose((echo(X,4,6) |transpose(shuffle(step((arpeggio(X) +((X+transpose(X,4) ) +transpose(X,7) ) ) ,12) ) ,4) ) ,12) ) ) |(((transpose((X+X) ,-5) +transpose((transpose(X,-5) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,12) ) ,12) ) +transpose(((((X|X) +transpose((X+X) ,12) ) +transpose(shuffle(arpeggio(X) ) ,4) ) +transpose(((X+X) +arpeggio(X) ) ,7) ) ,7) ) +transpose(arpeggio(transpose((transpose(X,-7) |(X+transpose(X,12) ) ) ,-5) ) ,12) ) ) ) ,4) |transpose(transpose((transpose(transpose(X,4) ,4) +X) ,-7) ,-5) ) +transpose(((((shuffle((step((((echo(X,4,6) +step(X,12) ) |X) |(((((arpeggio((X|X) ) +transpose((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(transpose(X,-7) ,7) ) ,4) ) +transpose(echo(shuffle(X) ,4,6) ,7) ) |((((X+transpose((X|X) ,4) ) +transpose(transpose(X,4) ,7) ) +echo(X,4,6) ) +transpose((X+transpose(X,7) ) ,4) ) ) +transpose(((X+transpose(X,7) ) +transpose(transpose((X+transpose(X,12) ) ,-7) ,7) ) ,4) ) +transpose((step(echo(transpose(X,-7) ,4,6) ,12) +(X+transpose(X,12) ) ) ,7) ) ) ,12) +transpose(shuffle(((transpose(X,-5) |((echo(X,4,6) +transpose(X,-7) ) +transpose((step(X,12) +transpose(X,12) ) ,7) ) ) +transpose(((transpose(transpose(X,-5) ,4) +transpose((transpose(X,4) +transpose(transpose(X,-7) ,7) ) ,12) ) +transpose((transpose((X+transpose(X,12) ) ,-5) +transpose(echo(X,4,6) ,-7) ) ,12) ) ,12) ) ) ,12) ) ) |((transpose((transpose(transpose(X,-5) ,-7) +transpose(((echo(echo(X,4,6) ,4,6) +transpose((X|arpeggio(X) ) ,4) ) +transpose(((X|X) +arpeggio(X) ) ,7) ) ,7) ) ,-5) +transpose(step((((X+transpose(transpose(X,-5) ,7) ) |X) +(((shuffle(X) |transpose(X,-7) ) +transpose(transpose(arpeggio(X) ,-5) ,4) ) +transpose(transpose(X,4) ,7) ) ) ,12) ,7) ) |(transpose(transpose(transpose(((transpose(X,-5) |transpose(X,4) ) +transpose((X|((X|X) +transpose(X,7) ) ) ,12) ) ,4) ,-5) ,-5) +shuffle(transpose(arpeggio((X+X) ) ,4) ) ) ) ) +(echo(transpose(transpose((((step((X|X) ,12) +transpose((arpeggio(X) +transpose(X,7) ) ,4) ) +transpose(transpose(X,-7) ,7) ) +(echo(step(X,12) ,4,6) +transpose(arpeggio((X+transpose(X,7) ) ) ,7) ) ) ,4) ,-7) ,4,6) +transpose((arpeggio(transpose(shuffle(transpose(X,-7) ) ,4) ) |step(shuffle(transpose(((X+X) +transpose(arpeggio((X|X) ) ,7) ) ,-7) ) ,12) ) ,12) ) ) |step((transpose(step((transpose((shuffle(echo(X,4,6) ) +transpose((((X+X) +transpose(shuffle(X) ,4) ) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) ,4) ) ,-5) +transpose(shuffle(shuffle(((transpose(transpose((X+X) ,4) ,-7) +transpose(transpose((X+X) ,-5) ,4) ) +transpose(transpose((((X+transpose(X,12) ) +transpose((X+transpose(X,7) ) ,4) ) +transpose(X,7) ) ,-5) ,7) ) ) ) ,12) ) ,12) ,-5) +transpose(echo(transpose(echo(((X+((X+X) +transpose((((X+transpose(X,12) ) +transpose((X+X) ,4) ) +transpose(echo(X,4,6) ,7) ) ,7) ) ) +transpose(transpose(shuffle(X) ,-5) ,7) ) ,4,6) ,4) ,4,6) ,7) ) ,12) ) +transpose((step((transpose(step(((transpose(echo((X+transpose(X,7) ) ,4,6) ,-5) +transpose(transpose((X|X) ,-7) ,7) ) +transpose(transpose(echo((X|X) ,4,6) ,4) ,7) ) ,12) ,4) |transpose((((transpose(X,4) +transpose(transpose(X,-7) ,7) ) +transpose(transpose(((transpose(transpose(X,4) ,-5) +transpose(transpose(X,4) ,4) ) +transpose((shuffle(((X+transpose(X,4) ) +transpose(X,7) ) ) +transpose((X|(X+X) ) ,12) ) ,7) ) ,-5) ,4) ) +transpose((transpose(((transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-5) +transpose(arpeggio(X) ,4) ) +transpose(transpose(X,-7) ,7) ) ,-7) |transpose(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-7) ,-7) ) ,7) ) ,4) ) ,12) |(((transpose(transpose(transpose(transpose(X,4) ,4) ,-5) ,-5) |((((transpose(transpose(X,4) ,-7) +transpose(transpose(X,-7) ,7) ) +transpose(step(((X+X) |echo(X,4,6) ) ,12) ,4) ) +transpose((arpeggio(transpose((X|X) ,4) ) +transpose((X+X) ,-7) ) ,7) ) +transpose(transpose((((X+X) +transpose(echo(X,4,6) ,7) ) |(X+X) ) ,-5) ,4) ) ) +transpose(transpose(transpose(transpose(X,-7) ,-7) ,4) ,-5) ) |transpose(shuffle(arpeggio((transpose((transpose(step(X,12) ,4) +transpose(transpose((X+transpose(X,7) ) ,4) ,12) ) ,-7) +transpose(arpeggio(step(X,12) ) ,12) ) ) ) ,4) ) ) ,12) ) ,12) ) ) ,12) ) +transpose((((step(((step((transpose(transpose(X,-5) ,-5) +transpose((step(transpose(transpose(((X+transpose(transpose(X,4) ,4) ) +transpose((X+X) ,7) ) ,-5) ,-5) ,12) +transpose(transpose((shuffle(transpose(X,-5) ) |(((X+X) +transpose(step(X,12) ,4) ) +transpose((X+X) ,7) ) ) ,4) ,7) ) ,7) ) ,12) |(((transpose(shuffle(X) ,-5) |(X+X) ) +((echo((X+step(X,12) ) ,4,6) |(((X+transpose(X,4) ) +transpose(X,7) ) +((X+X) +(X+transpose(X,7) ) ) ) ) +transpose(X,7) ) ) +transpose((step(step(((X+X) +transpose((X+X) ,7) ) ,12) ,12) +transpose(transpose((X|X) ,4) ,-5) ) ,12) ) ) +transpose(echo((transpose(transpose(echo((transpose(X,-7) |X) ,4,6) ,-7) ,-5) +transpose((arpeggio(((X|X) |(X+transpose((X+transpose(X,12) ) ,7) ) ) ) +echo(X,4,6) ) ,7) ) ,4,6) ,12) ) ,12) +transpose((((transpose(((transpose(transpose((transpose(X,-7) +transpose(transpose(X,4) ,7) ) ,4) ,-5) +transpose(transpose((transpose((X+X) ,4) |(X+transpose(transpose(X,4) ,12) ) ) ,-7) ,12) ) +((transpose(X,4) |transpose(arpeggio(X) ,-5) ) |transpose(transpose(transpose(echo((X+X) ,4,6) ,-5) ,-7) ,4) ) ) ,4) |step(transpose(arpeggio(transpose(transpose(transpose(X,-7) ,4) ,-5) ) ,-5) ,12) ) +transpose((transpose(transpose(step(((shuffle(((transpose(X,-7) +transpose(X,12) ) +(X+transpose(transpose(X,-5) ,7) ) ) ) +transpose(shuffle(shuffle(X) ) ,4) ) +transpose((transpose(X,4) |((transpose(arpeggio(echo(X,4,6) ) ,4) +transpose(transpose(X,-7) ,4) ) +transpose((((X+transpose((X|((X+transpose(X,4) ) +transpose(X,7) ) ) ,4) ) +transpose(((X+transpose(transpose(X,4) ,4) ) +transpose(X,7) ) ,7) ) +transpose(((X+arpeggio(X) ) +transpose(transpose(X,-7) ,12) ) ,7) ) ,7) ) ) ,7) ) ,12) ,-5) ,-7) +transpose(transpose(arpeggio((arpeggio((X+transpose(transpose(shuffle(((X+transpose(X,4) ) +transpose(X,7) ) ) ,-7) ,12) ) ) |step(transpose((transpose(X,-7) +(X|transpose(X,-7) ) ) ,4) ,12) ) ) ,-7) ,12) ) ,4) ) +transpose(echo(transpose((transpose(arpeggio(transpose(((step(transpose(X,-5) ,12) +transpose(transpose(((X+X) |transpose(X,-5) ) ,-7) ,7) ) +transpose(transpose((echo(X,4,6) +transpose(arpeggio((transpose(X,-5) +transpose(transpose(X,4) ,7) ) ) ,4) ) ,-5) ,12) ) ,-7) ) ,-5) +transpose(((transpose(transpose(((transpose((X|X) ,4) +transpose(X,4) ) +transpose((X|transpose(transpose(X,-7) ,-7) ) ,7) ) ,-7) ,4) +transpose(((((transpose(arpeggio(X) ,4) +transpose(shuffle((transpose(X,-7) +transpose(echo(X,4,6) ,7) ) ) ,4) ) +transpose(transpose(echo(transpose(X,-7) ,4,6) ,4) ,7) ) +transpose((transpose(transpose(transpose(transpose(X,-7) ,-5) ,-7) ,-5) +(X+transpose(echo(arpeggio(X) ,4,6) ,7) ) ) ,7) ) |transpose((X|X) ,-7) ) ,12) ) |step(((echo((transpose((transpose(X,-7) |echo(X,4,6) ) ,-5) +transpose((((X+transpose(X,4) ) +transpose((X+transpose(X,12) ) ,7) ) +transpose(transpose((X+transpose(X,12) ) ,-5) ,7) ) ,12) ) ,4,6) +transpose(transpose((transpose(transpose(transpose((X+X) ,-7) ,-5) ,4) +transpose(transpose(step(((X+transpose(X,4) ) +transpose(X,7) ) ,12) ,-5) ,12) ) ,4) ,7) ) +transpose(transpose((((((X+transpose(X,12) ) +transpose(step(X,12) ,4) ) +transpose((X+X) ,7) ) |shuffle(transpose((step(X,12) |((X+transpose(X,4) ) +transpose(X,7) ) ) ,-5) ) ) |((transpose(X,4) +transpose((X+transpose(X,12) ) ,12) ) |((X+X) +transpose(X,-5) ) ) ) ,-7) ,12) ) ,12) ) ,12) ) ,-7) ,4,6) ,7) ) ,4) ) +transpose(transpose(shuffle(transpose((echo(((arpeggio((transpose((X+transpose(X,12) ) ,-5) +transpose(step(((X+transpose(X,4) ) +transpose(X,7) ) ,12) ,7) ) ) +transpose(transpose(((echo(X,4,6) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) ) +transpose(transpose((X+transpose(X,12) ) ,-5) ,7) ) ,-7) ,4) ) +transpose(((X|(X+X) ) +transpose((transpose(X,-7) +transpose(transpose(X,4) ,12) ) ,12) ) ,7) ) ,4,6) +(((X|X) +transpose(((X+X) +transpose((X+transpose((X+transpose(X,12) ) ,7) ) ,12) ) ,4) ) +transpose(transpose((X+transpose(X,7) ) ,-5) ,7) ) ) ,-7) ) ,4) ,7) ) +transpose(shuffle(((((echo(echo(transpose(shuffle(transpose(echo(X,4,6) ,4) ) ,-5) ,4,6) ,4,6) +transpose(shuffle((((arpeggio((transpose(X,-5) +transpose((X+X) ,7) ) ) +transpose(transpose(transpose((X|X) ,-5) ,4) ,7) ) +transpose(((arpeggio(((echo(X,4,6) +transpose(shuffle(X) ,4) ) +transpose(X,7) ) ) +transpose(transpose(X,-5) ,4) ) +transpose(transpose(X,-7) ,7) ) ,7) ) +transpose(((step(step(X,12) ,12) +transpose(step(transpose(X,4) ,12) ,4) ) +transpose(arpeggio(transpose(X,-7) ) ,7) ) ,12) ) ) ,12) ) +transpose(transpose(transpose((((arpeggio(echo((transpose(transpose(((transpose(X,4) +transpose((X+transpose(X,7) ) ,4) ) +transpose(X,7) ) ,-7) ,4) +transpose(transpose((echo(transpose(X,-7) ,4,6) +echo(arpeggio(X) ,4,6) ) ,-7) ,12) ) ,4,6) ) +transpose(shuffle((transpose(((((step(X,12) +transpose(X,4) ) +transpose((X|X) ,7) ) |X) +transpose((X+(echo(X,4,6) +transpose(X,12) ) ) ,7) ) ,-5) +transpose(transpose(((transpose(arpeggio(X) ,4) |transpose((X+transpose(arpeggio(X) ,7) ) ,4) ) |(arpeggio(transpose(X,-5) ) +(X+transpose(echo((X+transpose(X,12) ) ,4,6) ,12) ) ) ) ,-7) ,7) ) ) ,4) ) +transpose((transpose(((X+X) +transpose(X,7) ) ,4) +transpose(transpose(((echo(transpose(X,4) ,4,6) +transpose((((((arpeggio(X) +transpose(step(X,12) ,7) ) +transpose(transpose(X,-7) ,4) ) +transpose((arpeggio(step(X,12) ) +(X+transpose(X,7) ) ) ,7) ) +transpose(transpose(arpeggio(shuffle(transpose(X,-7) ) ) ,-7) ,4) ) +transpose((((X+transpose(X,12) ) |(shuffle(X) +transpose((X+transpose(X,12) ) ,12) ) ) +transpose(transpose(step(X,12) ,-7) ,7) ) ,7) ) ,4) ) +transpose((X+transpose(X,12) ) ,7) ) ,4) ,7) ) ,7) ) +transpose(arpeggio((transpose(transpose((transpose((X+X) ,-7) |shuffle(X) ) ,4) ,-5) +transpose((X+X) ,12) ) ) ,12) ) ,-7) ,4) ,4) ) +transpose(transpose((transpose(transpose((X+transpose(step(step(X,12) ,12) ,12) ) ,-5) ,-5) +(transpose((echo(((X+transpose(X,4) ) +transpose(X,7) ) ,4,6) |echo((X+transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,12) ) ,4,6) ) ,-7) +transpose((((transpose(transpose(X,-7) ,4) |X) |transpose(transpose(echo(X,4,6) ,-7) ,4) ) +shuffle((transpose((X+X) ,-5) |transpose(((echo(transpose(X,4) ,4,6) +transpose(X,4) ) +transpose(arpeggio(X) ,7) ) ,-5) ) ) ) ,12) ) ) ,-7) ,7) ) +transpose((step((arpeggio(transpose((transpose(transpose(((arpeggio(X) +transpose((transpose(X,4) +transpose(X,-5) ) ,4) ) +transpose((arpeggio((X|X) ) +transpose(((X+X) |transpose(X,-5) ) ,7) ) ,7) ) ,-5) ,-5) +transpose(step((((X+transpose(X,7) ) +transpose(transpose(X,4) ,12) ) +transpose(((transpose(transpose(X,-7) ,4) +transpose((transpose(X,-5) |echo(X,4,6) ) ,12) ) |arpeggio(X) ) ,12) ) ,12) ,7) ) ,4) ) +transpose(((transpose(((shuffle((transpose(transpose((X+X) ,-5) ,-5) +transpose(((transpose(X,-5) |X) |(arpeggio(X) +(X+transpose(X,12) ) ) ) ,7) ) ) +transpose((arpeggio((X|(X+transpose(X,7) ) ) ) +transpose(transpose(transpose((X+transpose(X,12) ) ,-5) ,-7) ,12) ) ,4) ) +transpose(((X+transpose(X,7) ) +transpose(X,4) ) ,7) ) ,-5) +transpose(((transpose(arpeggio(((X+X) +transpose((X+transpose(X,12) ) ,12) ) ) ,-7) +transpose((((X|arpeggio(X) ) |((X+(X|X) ) +transpose(transpose(transpose(X,-7) ,4) ,12) ) ) +transpose(transpose((X+transpose(X,12) ) ,-5) ,4) ) ,12) ) |(transpose(echo(transpose((transpose(X,-5) +(X+transpose(X,7) ) ) ,4) ,4,6) ,-5) +transpose(step(((((shuffle(X) +transpose(X,4) ) +transpose(echo(X,4,6) ,7) ) +transpose(((X|X) |(X+transpose(X,12) ) ) ,12) ) |(X|(X|X) ) ) ,12) ,12) ) ) ,7) ) +transpose((transpose(transpose(((((X+transpose(X,4) ) +transpose(transpose(X,-7) ,7) ) +transpose(echo((X+transpose(X,12) ) ,4,6) ,12) ) |echo(X,4,6) ) ,4) ,-5) |(((((step(transpose(X,4) ,12) +echo(transpose(step(X,12) ,-7) ,4,6) ) +transpose(((((X+transpose(X,12) ) |echo(X,4,6) ) +(X+transpose((X+X) ,7) ) ) +X) ,12) ) +transpose(echo(transpose(arpeggio(X) ,4) ,4,6) ,4) ) +transpose((echo(step(transpose(X,-7) ,12) ,4,6) +transpose(((transpose(((X+X) +transpose(X,7) ) ,-5) +transpose(((transpose(X,-5) +(X+transpose(X,7) ) ) |transpose(transpose(X,-5) ,-7) ) ,4) ) +transpose((X+(X+transpose(X,7) ) ) ,7) ) ,7) ) ,7) ) +arpeggio(transpose(((X+transpose(X,12) ) +step(X,12) ) ,4) ) ) ) ,12) ) ,7) ) ,12) +transpose((step(arpeggio(((shuffle((step(X,12) |((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(transpose(X,4) ,4) ) +transpose(transpose(X,4) ,7) ) ) ) +transpose((echo((transpose(((X+X) |X) ,-7) +transpose(shuffle((X+X) ) ,7) ) ,4,6) +(((X|X) +transpose((transpose(X,-7) +(X+transpose(X,12) ) ) ,4) ) +echo(transpose(arpeggio((X+transpose(X,12) ) ) ,4) ,4,6) ) ) ,12) ) +transpose(transpose(((((echo(X,4,6) +transpose((X+transpose(X,7) ) ,7) ) +transpose(shuffle(transpose(shuffle(X) ,-5) ) ,7) ) +transpose((transpose(transpose((echo(X,4,6) +transpose(X,-5) ) ,-5) ,4) +(X+transpose(X,7) ) ) ,4) ) +transpose((((transpose((X+X) ,-7) +(X+transpose(X,12) ) ) +transpose(((X+X) +transpose(((X+X) +transpose((X+X) ,12) ) ,12) ) ,4) ) +transpose(transpose((transpose(X,4) +echo((X|X) ,4,6) ) ,-5) ,7) ) ,7) ) ,-7) ,12) ) ) ,12) +((((((transpose(((((X+transpose(X,12) ) +transpose(X,7) ) +transpose(X,4) ) +(transpose(transpose(X,-7) ,4) +shuffle(X) ) ) ,4) +transpose(transpose(((X|X) +(transpose(X,4) +transpose((X+transpose(X,7) ) ,12) ) ) ,-5) ,-7) ) +transpose((step((X+shuffle((X+transpose(transpose(X,-5) ,12) ) ) ) ,12) +transpose(((X|X) |(transpose((X+transpose(X,7) ) ,4) +transpose(((((X|X) +transpose(step(X,12) ,4) ) +transpose(X,7) ) |echo((X+X) ,4,6) ) ,7) ) ) ,-7) ) ,7) ) +step(transpose((arpeggio((X|X) ) |((X+transpose(X,12) ) |((X+transpose(X,7) ) +transpose((X+transpose(X,7) ) ,7) ) ) ) ,4) ,12) ) +transpose((shuffle(transpose(transpose(arpeggio((transpose(transpose(X,-5) ,-7) +transpose(echo(arpeggio(X) ,4,6) ,-5) ) ) ,-7) ,-5) ) +transpose(step(transpose(echo(X,4,6) ,-5) ,12) ,12) ) ,4) ) +transpose(transpose(transpose(echo(transpose(transpose(((transpose(X,-7) +X) |(X|X) ) ,-7) ,-7) ,4,6) ,4) ,-7) ,7) ) |transpose((transpose(arpeggio(transpose(echo((echo(X,4,6) +transpose(X,-7) ) ,4,6) ,-7) ) ,-7) +transpose((((arpeggio((transpose(shuffle(X) ,-7) +transpose(transpose(((arpeggio(X) |echo(X,4,6) ) |transpose(X,4) ) ,-5) ,7) ) ) |shuffle((transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-5) +transpose(step(transpose((transpose(X,-5) +transpose(transpose(X,-7) ,7) ) ,-7) ,12) ,7) ) ) ) +transpose(((((X+transpose(X,4) ) +transpose(X,7) ) |X) +transpose((X+transpose(arpeggio(X) ,7) ) ,7) ) ,4) ) +transpose(step((transpose(arpeggio(X) ,-7) +transpose((X+transpose(shuffle(X) ,-5) ) ,12) ) ,12) ,7) ) ,12) ) ,4) ) ) ,7) ) ,7) ) ) ,-5) ) ,12) )
random seed used was 131945177

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