Nancarrow is primarily known for his 50 studies for player piano, which combine a quasi-improvisatory likening to jazz pianists Art Tatum and Earl Hines, with dazzling rhythmic complexity rendered at tempos that exceed the capabilities of human performers. Nancarrow adopted the player piano as his instrument of choice because of its ability to exactingly reproduce his complex rhythmic layers -- sometimes up to 12 layers simultaneously -- and because of his relative isolation from performers while in Mexico. Nancarrow obtained a player piano in the 1940s and began laboriously hand-punching each note onto a piano roll, ultimately producing completed compositions.
Although in 1969 Columbia released an LP of several of his etudes, Nancarrow took no effort to promote his work until he was 59 years old. Motivated by a desire to show his teenaged son that he hadn't wasted his life, he visited the United States in 1981 to participate in the New American Music Festival in San Francisco. In 1982 he was composer in residence at the Cabrillo Festival, and subsequently toured in Europe. In 1982 he won a MacArthur Award (the so-called "genius grant").
Interest in his music increased in the 1980s. Some musicians began to transcribe the piano rolls into conventional musical notation. Guided by the rolls in grasping the rhythmic complexity, pianists Robert MacGregor, Joanna MacGregor, and Ursula Oppens began to perform some of the etudes. The dry wit and frequent warmth of the music comes through in live performance as they never have on a mechanical piano. Some of the more complex works have been arranged for two pianos or chamber ensembles by Yvar Mikhashoff, and played by such groups as the Arditti Ensemble and Ensemble Moderne.
Nancarrow's piano rolls and the player pianos were bought by the wealthy conductor and music collector Paul Sacher. Thus they have remained intact and archived together in the Sacher Foundation's extensive and well-protected archive of original musical documents.