Aeolian Variations (2014) was generated by my own Java program using a rule system according to which all the melodies, motives, and voice leadings are strictly regulated and pitch-class sets are transformed constantly throughout the piece so that they explore the entire 12-tone pitch space in various ways. Since the transformations are so dense and pitch-class sets alter every three seconds, the Java program employs a Lindenmeyer system to generate recurrent patterns, which make easier comprehension of the harmonies possible. In addition, the same, two-minutes long series of transformations of pitch-class sets is repeated four times, which results in the form of a theme and variations.
The frequencies of transformations of different types follow a Poisson-distribution. Assuming that wind levels and directions change in accordance with a Poisson distribution, the harmonies in this piece change as if they were produced by the Aeolian harp.
The program generated score files for the sound synthesis and processing software RTcmix and its channel vocoder and various filter instruments process the harp sounds and produce all the synthesized sounds.
The following is the first one-third of the piece (9'02"):