Jam Master Jay, whose sonic experiments with spacious drum breaks and grinding guitar riffs helped make Run-DMC the first hip-hop group to break into mainstream music, was killed in a shooting near the neighborhood where the trio grew up. He was 37.
Jay, whose real name was Jason Mizell, joined 20 years ago with Joseph "Run" Simmons and Daryl "DMC" McDaniels to form the group that would be more responsible than any other for spreading the idea that one person — a disc jockey — could provide the entire musical backdrop for a song.
"These are our Beatles," Public Enemy frontman Chuck D told The New York Times after Wednesday's shooting. He had once rapped, "Run-DMC first said a DJ could be a band."
The rise of the turntable enabled thousands of people to express themselves musically even if they lacked the instruments or resources to put together full bands.
"We always knew rap was for everyone," Mizell said in a 2001 interview with MTV. "Anyone could rap over all kinds of music."
All three members of the group grew up in middle-class homes in the Hollis neighborhood of New York's Queens borough. Simmons and McDaniels started out rapping at parties, and later invited Mizell to form a group with them.
Simmons' brother, Russell, had formed a small label — Def Jam — with producer Rick Rubin and signed early hip-hop stars including Kurtis Blow. The new group Joseph Simmons had formed with McDaniels and Mizell soon joined the roster.
While many early 80's hip-hop artists rapped over clean dance beats, Run-DMC and Rubin chopped up riffs from classic rock records for a grittier sound. The risk paid off with several rock-influenced hits, including "Rock Box" and "King of Rock."
But the sound finally exploded with audiences when the group remade the Aerosmith hit, "Walk This Way," creating hip-hop's biggest crossover success of the time.
Many fans and artists cite the song as the first rap record they ever heard, and rap and rock groups alike continue trying to recapture the song's mix of raw hooks and big beats punctuated by half-shouted lyrics.
Though rap videos were rare on MTV at the time, "Walk This Way," with its elaborate story line of a comical grudge match between rappers and rockers, was a constant fixture on the station for months.
The members of the group made an unforgettable impression with their black outfits and hats and white Adidas sneakers.
Raising Hell, the 1986 record that included "Walk This Way," "My Adidas," and "It's Tricky," sold more than 3 million copies, becoming the first rap album to go multiplatinum. The group's self-titled debut album in 1984 was the first rap album to go gold.
Mizell wasn't the first to manipulate records by scratching them in time under a needle. But he did become one of hip-hop's best known and most respected DJs through his deft scratching and the group's spirited promotion of his skills.
A song called "Jam Master Jay" announced, "We got the master of a disco scratch/there's not a break that he can't catch... Behind the turntables is where he stands/Then there is the movement of his hands/So when asked who's the best, y'all should say/Run-DMC and Jam Master Jay."
The group's cheerfully competitive wordplay had always promoted education and clean-living, but members were nonetheless linked to gang violence when fighting broke out on several stops of their national tour in support of Raising Hell.
Critics blamed the group and rap music for inciting fights between members of the Crips and Bloods gangs at California's Long Beach Arena. The trio condemned violence, and in 1986 called for a day of peace between warring Los Angeles street gangs.
"This is the first town where you feel the gangs from the minute you step into town to the time you leave," Mizell said.
The group later went on major tours with the Beastie Boys, Def Jam label mates who would eventually break the sales records they had set for hip-hop, and Public Enemy, the group that would create another musical revolution with its lyrics promoting black empowerment.
Violence continues to haunt hip-hop: Some of the genre's biggest stars, including Tupac Shakur and Christopher Wallace, also known as the Notorious B.I.G., have been shot to death.
The group has attempted several comebacks since Raising Hell, and had just completed a tour with Aerosmith and Kid Rock, one of the many performers who has tried to cop their mix of rap and rock.