He and John Cage both wrote percussion-dominated music and found new percussion instruments in automobile junkyards and import shops; one of their discoveries was the wonderful pitched ringing sound produced by brake drums. Harrison eventually went to the University of California at Los Angeles to work with its dance department. While there, he was a composition pupil of Arnold Schoenberg. Harrison had already developed a love of Renaissance and earlier music. He adopted the old dance form "estampie," a word he translates as "stampede" for his own stamping, highly rhythmic fast movements. In 1943, he moved to New York where he worked as a musician and writer. It was the unhappiest period of his life; he did not like the place, and found it difficult to make a living, although he did write some 300 music reviews for the Herald Tribune from 1944 to 1947. He developed a stomach ulcer and finally had a nervous breakdown. During this period, he made the acquaintance of Charles Ives and assisted the aged composer by editing and preparing for performance Ives' Third Symphony, which Harrison conducted at its premiere. Ives assisted Harrison financially when needed and, when the Third Symphony won the Pulitzer Prize in Music, Ives gave Harrison half the money. The 1947 nervous breakdown resulted in Harrison deciding to change his compositional style. He began to imitate the sounds of gamelan orchestra, which he had first heard at the 1939 Golden Gate Exposition. He studied Harry Partch's theoretical book Genesis of a Music (a gift from Virgil Thomson) and was convinced to adopt various forms of just-intonation rather than the standard 12-note scale. (He says he wishes musicians were numerically trained, so that he could say, for instance, "Cellos, you gave me a 10/9 there; please give me a 9/8 instead.")
Harrison subsequently resumed his high productivity, returned to the West coast in 1951 to settle for life in Aptos, California and continued to write music sounding primarily "Pan-Pacific" in style, often for unusual combinations of instruments. He first visited Asia in 1961 at a world music symposium, afterward, he became interested in establishing gamelan orchestras in North America, and devised an "American gamelan" made by his partner William Colvig from readily obtainable materials. He went on to write hundreds of compositions, and his works are often recorded. Harrison developed a system of musical organization based around melodic shapes he calls "melodicles" and analogous rhythmic patterns ("rhythmicals") and durations ("icti controls"). Lou Harrison died in 2003 en route to an Ohio festival dedicated to performances of his works.