Harry Partch (June 24, 1901 – September 3, 1974) was an American composer, music theorist, and creator of musical instruments. He composed using scales of unequal intervals in
just intonation, and was one of the first 20th-century composers in the West to work systematically with
microtonal scales. He built
custom-made instruments in these tunings on which to play his compositions, and described his theory and practice in his book
Genesis of a Music (1947).