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 13 generations the expression "X" became this:
((((step(((shuffle(transpose(((((X+X) +transpose(step(arpeggio(X) ,12) ,4) ) +transpose((X+transpose(X,7) ) ,7) ) +transpose(transpose(X,-7) ,12) ) ,-5) ) +transpose(transpose(transpose((transpose(X,-7) +transpose(transpose((X+transpose(X,12) ) ,4) ,7) ) ,-5) ,-7) ,4) ) +transpose(arpeggio(((transpose(((((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(X,4) ) +transpose(echo(X,4,6) ,7) ) |transpose(X,-7) ) +transpose(transpose(X,-7) ,7) ) ,-7) +transpose((step(echo(X,4,6) ,12) +transpose(shuffle(echo((X+X) ,4,6) ) ,12) ) ,4) ) +transpose(((transpose((((X+transpose(X,4) ) +transpose(X,7) ) +transpose((X+transpose(X,12) ) ,12) ) ,4) +transpose(X,4) ) +transpose(shuffle(transpose((step(X,12) +transpose((X+X) ,7) ) ,-7) ) ,7) ) ,7) ) ) ,7) ) ,12) +transpose(arpeggio(shuffle(arpeggio(echo(shuffle(X) ,4,6) ) ) ) ,4) ) +transpose((arpeggio(echo((step((X+transpose((X|X) ,12) ) ,12) |(transpose((transpose(X,-7) +transpose(X,12) ) ,4) +transpose(transpose(X,-7) ,12) ) ) ,4,6) ) +transpose(step(transpose((transpose(((shuffle(X) +transpose(transpose(X,4) ,4) ) +transpose(X,7) ) ,-5) |step(transpose(shuffle((X+transpose(X,7) ) ) ,4) ,12) ) ,4) ,12) ,7) ) ,7) ) |shuffle(arpeggio(((arpeggio(step(transpose(X,-7) ,12) ) +transpose(transpose((X+transpose(X,12) ) ,4) ,12) ) +(arpeggio(shuffle(((arpeggio(step(X,12) ) +transpose((X+transpose(X,7) ) ,12) ) +transpose((arpeggio(step(X,12) ) +X) ,12) ) ) ) +transpose(((transpose(step((X+X) ,12) ,4) +transpose(transpose((((X+transpose(shuffle(X) ,4) ) +transpose(X,7) ) +transpose((X+X) ,4) ) ,4) ,7) ) +transpose(transpose(((X+transpose(X,7) ) +transpose(echo(step(X,12) ,4,6) ,7) ) ,-5) ,7) ) ,12) ) ) ) ) ) +(echo((transpose(((X+transpose(X,12) ) +arpeggio(X) ) ,-7) +arpeggio(transpose(transpose(X,-7) ,-5) ) ) ,4,6) +((arpeggio(echo(transpose(transpose(X,-7) ,-7) ,4,6) ) +transpose(echo(transpose(((transpose(X,-7) +transpose((X+transpose(X,7) ) ,4) ) +transpose((X+transpose(X,12) ) ,7) ) ,-5) ,4,6) ,-5) ) |((((transpose(arpeggio(X) ,4) +transpose((X+X) ,7) ) +X) +transpose((transpose(X,-7) |transpose(X,-7) ) ,4) ) +transpose((((transpose(transpose(X,4) ,-7) +transpose(shuffle(X) ,12) ) +transpose((X+X) ,4) ) +transpose(step(X,12) ,7) ) ,7) ) ) ) )
random seed used was 8486 EXPR = transpose((shuffle((((X+transpose(X,12) ) +transpose(step(transpose(X,-7) ,12) ,7) ) +transpose(((arpeggio(shuffle(((step(shuffle(X) ,12) +transpose(transpose((X|X) ,4) ,4) ) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) ) ) +transpose(step((X+transpose(transpose(((X+X) +transpose(X,7) ) ,4) ,12) ) ,12) ,4) ) +transpose(shuffle(((transpose(((X+transpose(X,12) ) +transpose(transpose((X+transpose(X,12) ) ,-7) ,7) ) ,4) +transpose((step(transpose(X,-7) ,12) +(X+transpose(transpose(X,-7) ,7) ) ) ,4) ) +transpose((arpeggio(step(X,12) ) |shuffle(X) ) ,7) ) ) ,7) ) ,7) ) ) +transpose(transpose((((shuffle(step(echo(((X+transpose(X,12) ) +(X+transpose(X,12) ) ) ,4,6) ,12) ) +transpose(step((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(echo(X,4,6) ,12) ) ,12) ,4) ) +transpose(step(echo(transpose((X+transpose(X,7) ) ,4) ,4,6) ,12) ,7) ) +transpose(shuffle(((X|X) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,12) ) ) ,7) ) ,-5) ,12) ) ,-7)
random seed used was 0 EXPR = (((((transpose(transpose((X+transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) ,-5) ,4) +transpose(((shuffle(transpose(X,-7) ) +arpeggio((X+transpose(X,12) ) ) ) +transpose((shuffle(shuffle(X) ) +transpose((arpeggio(((X+transpose(X,7) ) +X) ) |transpose(echo(X,4,6) ,4) ) ,12) ) ,7) ) ,12) ) +transpose(echo(transpose((shuffle(step(((((X+transpose(X,7) ) +transpose(X,4) ) +transpose(X,7) ) |shuffle((X+X) ) ) ,12) ) +transpose(step(transpose((X+X) ,-7) ,12) ,7) ) ,-7) ,4,6) ,4) ) +transpose(echo(transpose((echo(transpose(transpose(X,-7) ,-7) ,4,6) +transpose(((((X+transpose(X,4) ) +transpose(X,7) ) |shuffle(X) ) +((X+transpose(transpose(X,4) ,4) ) +transpose(transpose(X,-7) ,7) ) ) ,7) ) ,4) ,4,6) ,7) ) +transpose(echo((transpose(((echo(X,4,6) +transpose(X,4) ) +transpose(echo(X,4,6) ,7) ) ,-5) |(((transpose((echo((echo(X,4,6) +(X+X) ) ,4,6) +(X+transpose(X,12) ) ) ,-5) +step(arpeggio(X) ,12) ) +transpose((echo((echo(X,4,6) +transpose(arpeggio(X) ,7) ) ,4,6) +transpose(transpose(echo((X+transpose(X,12) ) ,4,6) ,4) ,7) ) ,4) ) +transpose(((transpose(transpose(X,4) ,-7) +transpose((shuffle(X) +transpose(X,7) ) ,4) ) +transpose(arpeggio(transpose(X,-7) ) ,7) ) ,7) ) ) ,4,6) ,7) ) +transpose((echo((((((((arpeggio(X) +transpose((X+X) ,12) ) +transpose((((X+transpose((X+transpose(X,12) ) ,4) ) +transpose(transpose(X,4) ,7) ) +transpose(transpose(shuffle(X) ,4) ,7) ) ,4) ) +transpose(transpose(arpeggio((X+transpose(X,7) ) ) ,-7) ,7) ) +transpose(shuffle(step(shuffle(X) ,12) ) ,12) ) +transpose(((step((arpeggio(X) |X) ,12) +transpose((transpose(X,-5) +X) ,4) ) +transpose(transpose((((X|X) +transpose(transpose(X,-7) ,4) ) +transpose(arpeggio(X) ,7) ) ,-7) ,7) ) ,12) ) +transpose((transpose(transpose((X+transpose(X,7) ) ,-7) ,4) +transpose(echo(echo(X,4,6) ,4,6) ,-7) ) ,12) ) +transpose((echo(transpose(step(X,12) ,-5) ,4,6) +(transpose(transpose(((X|X) +transpose(arpeggio(X) ,7) ) ,-7) ,-7) +transpose((transpose(((X|X) |X) ,-7) +(((X+X) +transpose((X+X) ,4) ) +transpose((X+transpose(X,12) ) ,7) ) ) ,12) ) ) ,7) ) ,4,6) +(shuffle((arpeggio((((transpose(X,-7) |X) +transpose(transpose(X,-7) ,4) ) +transpose(transpose((X+X) ,4) ,7) ) ) +transpose(echo((shuffle(((X+transpose(X,4) ) +transpose(X,7) ) ) |arpeggio(X) ) ,4,6) ,12) ) ) +transpose((arpeggio(transpose(transpose((((X+(X|X) ) +transpose(echo(transpose(X,4) ,4,6) ,12) ) |(transpose(transpose(X,-7) ,-7) |echo(transpose(X,-7) ,4,6) ) ) ,4) ,-7) ) +((transpose((X+transpose(X,12) ) ,-7) +transpose((transpose(((X+transpose(X,12) ) +transpose(X,7) ) ,4) |(arpeggio(arpeggio(X) ) |((X+transpose((X|X) ,4) ) +transpose(step(X,12) ,7) ) ) ) ,7) ) +(transpose(transpose((X|X) ,-7) ,4) +transpose(((((X+transpose(X,4) ) +transpose(X,7) ) +transpose((X+transpose(X,7) ) ,7) ) +transpose((transpose(X,-7) +transpose(X,7) ) ,7) ) ,7) ) ) ) ,7) ) ) ,7) )
random seed used was 0 EXPR = (((transpose(step(step(step((transpose(shuffle((X|X) ) ,-7) +transpose(((X+X) +transpose(X,12) ) ,7) ) ,12) ,12) ,12) ,-7) +transpose(step((((transpose(echo(step(X,12) ,4,6) ,4) +((X+transpose(X,7) ) |(transpose(X,-5) +transpose((X+X) ,12) ) ) ) +transpose(arpeggio(echo((shuffle(X) +transpose(shuffle(X) ,12) ) ,4,6) ) ,4) ) +transpose((((transpose(((step(arpeggio(X) ,12) +transpose(arpeggio(arpeggio(X) ) ,12) ) +transpose(transpose((transpose(X,4) +transpose(X,12) ) ,-5) ,12) ) ,-7) +transpose(((echo(transpose(X,-7) ,4,6) +transpose(echo(step(X,12) ,4,6) ,4) ) +transpose((step(X,12) +transpose((X+transpose(X,12) ) ,12) ) ,7) ) ,12) ) +transpose((((X+X) +transpose(transpose(transpose((X+transpose(X,12) ) ,-7) ,4) ,12) ) +transpose((((transpose(X,4) +transpose(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-5) ,4) ) +transpose(transpose(arpeggio(X) ,-7) ,7) ) +transpose((((X|X) +transpose(step((X+X) ,12) ,4) ) +transpose((X|X) ,7) ) ,7) ) ,7) ) ,4) ) +transpose((((transpose((((step(transpose(X,-5) ,12) +transpose(((transpose(X,4) +transpose(transpose(X,4) ,4) ) +transpose(X,7) ) ,4) ) +transpose(arpeggio(X) ,7) ) +transpose(((echo(X,4,6) +transpose((X+transpose(X,12) ) ,4) ) +transpose((X+transpose(X,7) ) ,7) ) ,7) ) ,4) +transpose((step((X+transpose(X,7) ) ,12) +transpose(arpeggio(transpose(X,-7) ) ,7) ) ,4) ) +transpose(transpose(transpose(((X|X) +transpose(arpeggio(X) ,7) ) ,-7) ,-7) ,7) ) +transpose(transpose(transpose(transpose((X|X) ,-5) ,-7) ,4) ,12) ) ,7) ) ,7) ) ,12) ,12) ) +transpose(((echo(step(shuffle(transpose(arpeggio((step(echo(X,4,6) ,12) +transpose(transpose(transpose(transpose(X,-7) ,-7) ,-7) ,12) ) ) ,-7) ) ,12) ,4,6) +transpose(((((transpose(transpose(step(shuffle(X) ,12) ,-7) ,-7) +transpose((transpose(shuffle(arpeggio(transpose(X,-7) ) ) ,-7) +transpose((transpose(transpose(X,-7) ,-5) +transpose(transpose(X,-7) ,12) ) ,7) ) ,4) ) +transpose(((transpose(shuffle(X) ,-7) |shuffle((X+transpose(X,7) ) ) ) +transpose(((((transpose(transpose(X,-7) ,4) +transpose((X+transpose(X,7) ) ,4) ) +transpose(shuffle(X) ,7) ) +transpose(arpeggio(((X+transpose(X,4) ) +transpose(X,7) ) ) ,4) ) +transpose(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-7) ,7) ) ,7) ) ,7) ) +transpose(step((X+transpose(transpose((X+X) ,-5) ,7) ) ,12) ,4) ) +transpose((((((X+transpose(X,7) ) +transpose(((step(X,12) +transpose((echo(X,4,6) +transpose(X,7) ) ,4) ) +transpose(step(X,12) ,7) ) ,4) ) +transpose(step((X|X) ,12) ,7) ) +(transpose(transpose(X,-7) ,-5) +(((X+transpose(X,7) ) +transpose(X,4) ) +transpose((X+transpose(X,12) ) ,7) ) ) ) +echo((((X+transpose(step(X,12) ,4) ) +transpose((shuffle(X) |X) ,7) ) +transpose((transpose(X,-7) +transpose(echo(transpose(X,-5) ,4,6) ,12) ) ,7) ) ,4,6) ) ,7) ) ,-7) ) +transpose(shuffle(echo(echo((((transpose(X,4) +transpose(X,7) ) +transpose(X,12) ) +transpose(step(transpose(X,-7) ,12) ,12) ) ,4,6) ,4,6) ) ,7) ) ,4) ) +transpose(transpose((shuffle(transpose(transpose(((arpeggio(X) +shuffle(X) ) +echo(X,4,6) ) ,-7) ,4) ) |arpeggio(arpeggio((transpose(echo(X,4,6) ,-7) |(X+transpose(echo(X,4,6) ,7) ) ) ) ) ) ,-5) ,7) )
random seed used was 0

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