ESP-Disk is a New York-based record label, founded in 1964 by lawyer Bernard Stollman.

From the beginning, the label's goal has been to provide its recording artists with complete artistic freedom, unimpeded by any record company interference or commercial expectations—a philosophy summed-up by the ESP motto, printed on every release: “The artists alone decide what you will hear on their ESP-Disk”.

Though it originally existed to release Esperanto-based music, starting with its second release (Albert Ayler's Spiritual Unity), ESP became the most important exponent of what is commonly referred to as free jazz. ESP also released recordings by uncommercial underground rock acts including the Fugs, The Godz and Pearls Before Swine. Though it suspended releasing records in the 70s, several new releases by iconic and cutting edge artists have been released by the label, and it still exists with nearly its entire catalog available.

Other artists who have recorded for this label include Ornette Coleman (the "Town Hall Concert"), Pharaoh Sanders (who made his recording debut on ESP), Sun Ra, Ronnie Boykins, Marion Brown, Sonny Simmons, Paul Bley, Ran Blake, and Perry Robinson.

Pharoah Sanders (born October 13, 1940) is a Grammy Award–winning American jazz saxophonist.

Saxophonist Ornette Coleman once described him as "probably the best tenor player in the world." Emerging from John Coltrane's groups of the mid-1960s Sanders is known for his overblowing, harmonic, and multiphonic techniques on the saxophone, as well as his use of "sheets of sound." Sanders is an important figure in the development of free jazz; Albert Ayler famously said: "Trane was the Father, Pharoah was the Son, I am the Holy Ghost."

Born Ferrell Sanders in Little Rock, Arkansas, he began his professional career playing tenor saxophone in Oakland, California. He moved to New York City in 1961 after playing with rhythm and blues bands. He received his nickname "Pharoah" from bandleader Sun Ra, with whom he was performing. After moving to New York, Sanders had been destitute: "[H]e was often living on the streets, under stairs, where ever he could find to stay, his clothes in tatters. Sun Ra gave him a place to stay, bought him a new pair of green pants with yellow stripes (which Sanders hated but had to have), encouraged him to use the name 'Pharoah', and gradually worked him into the band."

Giuseppi Logan (born May 22, 1935) is a jazz musician originally from Philadelphia, Pennsylvania who taught himself to play piano and drums before switching to reeds at age 12. At the age of 15 he began playing with Earl Bostic and later studied at the New England Conservatory. In 1964 he relocated to New York and became embroiled in the free jazz scene.

Logan played alto and tenor saxophone, bass clarinet, flute, piano and Pakistani oboe. He collaborated with Archie Shepp, Pharoah Sanders and Bill Dixon before forming his own quartet made up of pianist Don Pullen, bassist Eddie Gomez and percussionist Milford Graves. After Pullen's departure, pianist Dave Burrell joined the group. Logan was a member of Byard Lancaster's band and toured with and appeared on records by Patty Waters. He recorded two albums for the ESP Disk record label and later appeared on an album by Roswell Rudd on the Impulse! label. A 1965 press release from ESP-Disk indicates that a third album was planned, but never released, possibly due to Logan's increasingly erratic behavior. This title was supposed to have been ESP-1018, "The Giuseppi Logan Chamber Ensemble In Concert", but this catalogue number was eventually assigned to an album by The Fugs.

Alan Sondheim is an American poet, critic, musician, artist, and theorist of cyberspace.

Alan Sondheim was born in Wilkes-Barre, Pennsylvania. He holds a B.A. and M.A. in English from Brown University. He lives with his partner, Azure Carter, in Brooklyn, New York.

Sondheim's books include the anthology Being on Line: Net Subjectivity (Lusitania, 1996), Disorders of the Real (Station Hill, 1988), .echo (alt-X digital arts, 2001), Vel (Blazevox, 2004-5), Sophia (Writers Forum, 2004) and The Wayward (Salt Publishing, 2004), as well as numerous other chapbooks, ebooks, and articles. Sondheim has long been associated with the Trace online writing community, and was their second virtual-writer-in-residence. His video and filmwork have been widely shown.

Sondheim co-moderates several email lists, including Cybermind, Cyberculture and Wryting. Since 1994, he has been working on the "Internet Text," a continuous meditation on philosophy, psychology, language, body, and virtuality. His artwork can also be found within Second Life.

Charles Gayle (born February 28, 1939) is a free jazz saxophonist, pianist, bass clarinetist, and percussionist.

Charles Gayle was born in Buffalo, New York. Some of Gayle's history is unclear. He was apparently homeless for approximately twenty years, playing saxophone on street corners and subway platforms around New York City. In 1988, he gained fame through a trio of albums recorded by a Swedish label, Silkheart Records. Since then he has become a major figure in free jazz, recording for labels including Black Saint, Knitting Factory Records, FMP, and Clean Feed. He has also taught music at Bennington College.

Gayle's music is spiritual, and heavily inspired by the Old and New Testaments. He has explicitly dedicated several albums to God. His childhood was influenced by religion, and his musical roots trace to black gospel music. After his church experiences, Gayle credits among his influences Louis Armstrong, John Coltrane, Albert Ayler, Thelonious Monk, and Art Tatum. He has performed and recorded with Cecil Taylor, William Parker, and Rashied Ali.