Perhaps hyperbolically described as a clubland "legend", Jay is certainly a hugely popular and highly respected figure in dance music. As a DJ, his style encompasses many forms of black music, including soul, funk, disco, hip-hop and garage. Perhaps his enduring popularity (the UK's Muzik magazine called him a "man of the people") lies in this rare democratic approach to his playlist. Another factor is his foresight and innovation: Jay was listening to early Chicago house records and staging warehouse parties three years before the UK's acid house explosion of 1988. He is also the "DJ's DJ", with many contemporary superstar DJ's citing him as an early influence.

Jay was born in the early 60s to West Indian parents. He had DJing ambitions even at the tender age of eight and first "played out" at his cousin's 10th birthday party. As he matured, he was inspired by the American R&B of the late 60s, especially the sound of Sly And The Family Stone, Aretha Franklin and James Brown. By the late 70s, he had become an almost obsessive collector of US black music, collecting Motown Records, Stax Records, Atlantic Records, Salsoul and jazz recordings. He witnessed the disco phenomenon first-hand while visiting family in New York. One of his relatives was a successful Brooklyn DJ and Jay stayed for several months, visiting the seminal Paradise Garage and forming friendships with Larry Levan, Timmy Regisford, Tee Scott and then later, David Morales, Tony Humphries and Little "Little" Louie Vega before they had been heard of in the UK. Jay was inspired to take up DJing more seriously and began to build the Good Times sound system with his brother Joey to play at the Notting Hill Carnival. With his reputation and audiences growing steadily, he and Gordon Mac started a pirate radio station, Kiss FM (named after its US predecessor) in 1985.

Jay's reputation and influence attracted many talented DJs to the station, several of whom have since become household names: Jonathon More and Matt Black (Coldcut), Jazzie B. (Soul II Soul), Dr. Bob Jones, Danny Rampling, Trevor Nelson, Gilles Peterson and his partner and protégé, the ubiquitous Judge Jules. Jay and Jules were the originators of the rare groove scene, staging warehouse parties as Shake And Fingerpop and Family Funktion respectively, and playing a mixture of classics and early house records. The arrival of acid house brought dance music to a much larger audience and by 1990, Kiss FM had received a license to broadcast legally. Jay also established the UK's first garage-style club, High On Hope, playing host to US talent such as Tony Humphries, Marshall Jefferson, Blaze, Ten City and Adeva. PolyGram Records sought the skills of Jay and Gilles Peterson to launch their new subsidiary, Talkin' Loud Records, whose early signings included Omar, Bryan Powell, the Young Disciples, Galliano and Incognito. Jay has played all over the world and is often hired for celebrity parties, fashion shows and film premieres and has won numerous awards. The Face magazine once described him as a "clubland institution".