Jon Hassell (born March 22, 1937) is an American trumpet player and composer. He is known for developing the musical concept known as “Fourth World,” which sees him unify ideas from minimalism, various world music sources, and his electronic manipulation of the trumpet. He has collaborated with artists such as Brian Eno, the Theatre of Eternal Music, Talking Heads, Farafina, Peter Gabriel, Ani DiFranco, and Ry Cooder.

Born in Memphis, Tennessee, United States, Hassell received his master’s degree from the Eastman School of Music in Rochester, New York. During this time he became involved in European serial music, especially the work of Karlheinz Stockhausen, and so after finishing his studies at Eastman, he enrolled in the Cologne Course for New Music (founded and directed by Stockhausen) for two years. Hassell returned to the U.S. in 1967, where he met Terry Riley in Buffalo, New York and performed on the first recording of Riley’s seminal work In C in 1968. He pursued his Ph.D.in musicology in Buffalo and performed in La Monte Young‘s “Dream House” (a.k.a. Theatre of Eternal Music) in New York City.