XXL celebrates 50 years of hip-hop with this moment:

Jan. 3, 1991: Main Source kicked off the new year with the release of their classic debut album, Breaking Atoms. The 14-song collection is remembered as one of the last seminal albums of the golden age of hip-hop.

The group consists of producer and rapper Large Professor, and Toronto DJs and producers Sir Scratch and K-Cut. Breaking Atoms is regarded as an influential album in hip-hop for introducing the production abilities of Large Professor and marking the debut of legendary Queens, N.Y. rapper Nas.

Noted for its rich, jazzy sonics and intricately layered percussion, Breaking Atoms would spawn several hit singles. The lead single, "Looking At The Front Door," would reach the No. 1 spot on the Billboard Hot Rap Singles chart while the follow-up, "Just Hangin' Out", would peak at No. 11.

However, the album’s most famous moment might be the iconic guest appearance from a then-unknown MC named Nas. His visceral rhymes on the posse cut "Live at the Barbecue" featuring Akinyele and Joe Fatal is widely remembered as one of the greatest debuts in hip-hop history.

"Verbal assassin, my architect pleases/When I was twelve, I went to hell for snuffin' Jesus," Nas spits on the stellar track. "Nasty Nas is a rebel to America/Police murderer, I'm causin' hysteria/My troops roll up with a strange force/I was trapped in a cage and let out by the Main Source."

The musical influence of Main Source is undeniable. Not only because it launched the career of Nasir Jones, but because producer Large Professor has gone on to become one of the most celebrated producers of all time. The veteran track master has produced songs for Mobb Deep, Busta Rhymes, Eric B. & Rakim , Kool G. Rap and, of course, Nas’ masterful 1994 debut album, Illmatic.

Watch Main Source's "Looking at the Front Door" Video Below

Watch Large Professor and Nas Perform "Live at the Barbecue" Live at SXSW Below

Listen to Main Source's Classic Debut Album Breaking Atoms Below

See Rappers' Real Names

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