MuseRND

MUseRND composes music from pure randomness. Every note of the melody, every chord, bass note, drum hit and extra instrument starts life as random bytes read from /dev/urandom. An evolutionary search then breeds those bytes, keeping the variations that a set of music-theory detectors rate as more musical, until a song emerges. Nothing is copied from existing music and no notes are written by rules: the rules only judge, the randomness creates.
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Songs are saved as Standard MIDI and uncompressed MusicXML, ready for any DAW, notation program or synthesizer, together with the genome (the evolved bytes) so every song can be rebuilt exactly. A browser UI lets you compose, listen, edit and keep a library of songs.