Jason William Mizell (January 21, 1965 – October 30, 2002), also known as Jam-Master Jay, was the DJ of the influential hip hop group Run-D.M.C. He helped define the sound of the band and the style of the black hats and Adidas shoes that became synonymous with their name. During the 1980s, Run-D.M.C. became the biggest hip-hop group and are credited with breaking hip-hop into mainstream music.He started DJing at the age of 13. He first started playing at parks and later played at bars.Once he got a pair of Technics 1200s he improved rapidly since he was able to practice at night with headphones on when he was supposed to be sleeping.

Mizell became a DJ because he “just wanted to be a part of the band”.Prior to joining Run-D.M.C. he played bass and drums in several garage bands. In 1982 he hooked up with Joseph “Run” Simmons and Darryl “D.M.C.” McDaniels just after they graduated from high school and agreed to DJ for them because he wanted to be part of the band. On Run-D.M.C’s album Raising Hell, Mizell played keyboards, bass, and live drums in addition to his turntable work. Mizell remained in his childhood neighborhood in Hollis, Queens his entire life.

In 1989, Mizell established the label Jam Master Jay Records, which scored a success in 1993 with the band Onyx.He also connected Chuck D with Def Jam co-founder Rick Rubin. After achieving relative prominence, Mizell was known to use the alias Jay Gambulos so as to avoid unwanted public attention.He is also related to the Mizell Brothers, a popular production team for Gary Bartz (Tramadol), Johnny “Hammond” Smith, and others.

In 2002, Mizell founded the ‘Scratch DJ Academy’ in Manhattan to “provide unparalleled education and access to the art form of the DJ and producer.