They chatted with a 16-year-old star-to-be named the Notorious B.I.G.; introduced Nas before his breakthrough, “Illmatic”; and hosted Jay Z several times before he released an album.
Some of the biggest names in rap emerged from New York in the 1990s after getting the stamp of approval from an unlikely pair of gatekeepers: Adrian Bartos and Robert Garcia, friends, roommates and hip-hop obsessives who hosted “The Stretch Armstrong and Bobbito Show” for eight years on the Columbia University radio station, WKCR.
When they started the weekly program in 1990, Mr. Bartos (known as Stretch) and Mr. Garcia (Bobbito) were music-industry newcomers who had very little idea what they were doing. (“I was a goofy nerd,” Mr. Garcia said in an interview this week.) But their appreciation of hip-hop culture and ability to sniff out talent made their partnership an essential part of hip-hop history, one that has been documented in a new film, “Stretch and Bobbito: Radio That Changed Lives.” (The movie is screening at the Maysles Cinema in Harlem through Sunday.)
“Stretch and Bobbito — that was our dream,” says Eminem in the movie. “The fact that we even had a chance to go and be on it was crazy.”
Jay Z calls an appearance on the show “one of those moments that people would talk about in hip-hop lore.” He added, “I was just happy about being on the radio.”
Stretch, 46, and Bobbito, 49, were immersed in hip-hop culture thanks to childhoods in the melting pot of Upper Manhattan.
“I didn’t really choose hip-hop, it chose me,” Stretch said. “I was compelled to get into it.”
The two met at the record label Def Jam, where Bobbito was working in A&R and Stretch was hunting down promos to play at nightclub D.J. gigs. Stretch, who was planning to attend Columbia University, approached WKCR about doing a rap show over the summer of 1990. The show had its premiere on Oct. 25.
“I didn’t know if I had the right to represent rap music,” Bobbito said. “But the immediacy of the response was enlightening. It was like, ‘Wow, not only am I meant to be here, but I’m being applauded by the most hard-rock dudes.’ They could easily be like, ‘Who is this nerd dude?’ ”
Radio has long been essential to hip-hop, particularly in the pre-Internet days, when an artist’s best hope for reaching a broad audience was radio play. D.J.’s like Red Alert on WRKS and Mr. Magic on WBLS introduced the nascent genre to listeners in the ’80s, and many became lifelong devotees.
“Radio was the only place you could hear the culture happening live, in real time,” said Angie Martinez, the New York radio luminary who was a star broadcaster on Hot 97 when it became the most important radio station for rap in the ’90s.
“Everything we were doing on radio at that point was influenced by them,” said Peter Rosenberg, one of Hot 97’s current D.J.s. “The best compliment I got was that right away, I got compared to them.”
Like many great musical partnerships, Stretch and Bobbito struggled with creative differences, and in 1998, Stretch left WKCR, partly because of tensions over playlists. But off the air, the two reconciled, and Stretch was invited back to the show to say a final goodbye in 2002.
Bobbito went on to make a film about the world of street basketball that attracted the attention of a producer named Omar Acosta, who saw it on PBS and contacted Bobbito. Three days later, they shot the first scene for the Stretch and Bobbito documentary, and began tracking down hip-hop stars from the show’s glory days.
The new film joins “Style Wars,” “Stations of the Elevated” and “Big Fun in the Big Town” in documenting rap’s emergence in New York City.
Since the filmmakers had a relatively small amount of video footage from the radio show, artists, including José Parlá, illustrate scenes, and photographs and scenes from the era provide a visual accompaniment to the music from the show.
“When people listened to our show, there was no illustration,” Bobbito said. “People heard Biggie the first time in 1991, as a teenager with no deal; no one knew what he looked like. That meant, in this film, I could put whatever B-roll I want.”
Though they are known for helping to break blockbuster artists, Stretch and Bobbito also had plenty of guests whose names elicit shrugs today. Bobbito said that he could never tell who was destined for mainstream success
“In 1995, Jay Z was hustling, he was arrogant as all hell,” Bobbito said. “I was always amazed, like, why is this dude so cocky? He hasn’t sold a record yet. But obviously that confidence was coming from other areas of his life, and also he just had this vision.
“We had so many artists come through our show that had the same confidence,” he continued. “And they never got signed, never put out records, or never sold. So people ask me, ‘Did you know?’ And no, we didn’t know. There was constantly that question mark about whether a dude was going to blow up. And that’s what made the show special.”
An earlier version of this article misstated the given name of a producer of the film. He is Omar Acosta, not Oscar.