"Rap is out of the fad era now, right?" asks Kurtis Blow rhetorically. "We're going on seven years ago, because it was '79 when the first rap records came out. Usually, it takes a 10-year period before people begin taking something seriously as a viable form of music."

It's true that rap music wasn't taken too seriously when it first emerged. In fact, even after the Sugarhill Gang "Rapper's Delight" went triple platinum, most record industry trade publications still looked at the style as a form of novelty music. Yet rap has proven to be not only durable but also adaptable. Musically, it has absorbed everything from the latest high-tech electronics to the grungiest heavy metal guitar, while rappers themselves are turning up in everything from movies to package tours like Sunday's Capital Center show featuring Blow, Doug E. Fresh, Trouble Funk, EU and others.

Through it all, Kurtis Blow has remained a dominant force. His "Christmas Rappin'," released in 1979, was one of the first rap records to be put out by a major label, selling more than 400,000 copies. Five albums and many singles later, Blow still sounds, in street parlance, "fresh."

"Yeah, you could say I'm fresh," he agrees without undue modesty. "I guess it's basically just knowing what's happening, traveling around and keeping my ear to the street. Just being out there."

Of course, Blow picks up a lot more than rhymes and rhythms from the streets. For instance, there were the two kids from Hollis, Queens -- Joe Simmons and Daryll McDaniels -- who wanted to record a couple of raps. Blow agreed to help out with their single, coming up with a mix that was mostly beat box and voice, a sound that was then common on the streets but rare on record. As a result, "It's Like That" was an instant smash, launching Run-D.M.C., as Simmons and McDaniels are known, on one of rap's most successful careers.

"When I made my first record, Run Simmons was my DJ," Blow says. "His older brother, Russell Simmons, is my manager."

If the relationship between Blow and the Simmons brothers sounds a bit familiar, it may be because it's part of the plot to "Krush Groove." The film, which stars Blow, Run-D.M.C., Sheila E. and the Fat Boys, is a thinly disguised version of the real-life adventures of Russell Simmons' Rush Groove productions. (While actor Blair Underwood portrays Krush Groove's aggressive boss, the real Russell Simmons can be seen playing his sidekick).

Although Blow's role, like those accorded the other rappers, isn't exactly on a level with playing Hamlet, it has earned him a fair amount of attention. "I've been pursuing an acting career, and since the movie's been doing real well," he says, "I've gotten a couple of offers, nothing real solid yet."

To be honest, Blow was upstaged in the film by the Fat Boys, a rotund rap trio whose gift for comedy more than matches their way with words. Not that this fazes him, because the Fat Boys are another set of Blow's prote'ge's.

"I met them when they won the Tin Pan Apple Rap and Dance Contest back in '83," he recalls. "They put out a record called 'Reality,' which didn't do so well. So their manager called me and asked if I would produce their record. He came up with the idea of calling them the Fat Boys -- they were originally the Disco Three -- and wanted to make a Fat Boy record, talking about how much they could eat and like that."

Blow's abilities behind the board also landed him the coproducer's spot on a project very close to his heart, the all-star single "King Holiday." Featuring Kool and the Gang's James Taylor, Whitney Houston, El DeBarge, Stephanie Mills, the Fat Boys, Run-D.M.C., Melle Mel and others, the song is, as Blow puts it, "a dance ballad."

"It's a celebration record; we're celebrating that this January, Martin Luther King Day will be an actual holiday for the first time. A lot of people had been fighting very extensively for the holiday -- Stevie Wonder, Coretta Scott King, the whole King family -- since back in '68. So there's a lot of feeling behind it. It's a great record."

Still, for all his success as a rapper and producer, Blow remains a little wary of playing Washington. It isn't the audiences that worry him, but the go-go bands that invariably open for him. "I went to Washington with my first band in '81," he says, "and that was the first time I ever played with Trouble Funk. And they tore the house down. Totally.

"I was pretty hot then -- with 'The Breaks' and a new album, my name was still buzzing. But they really tore the house down, and every time after that, when I would go to Washington I would get my butt kicked by Trouble Funk, Rare Essence, any local band I would play with. They would just stomp, and the crowds would sit down until you played that percussion stuff."

So, unable to beat them, Blow joined them, adding a go-go beat to his sound that can be heard on his new single, "If I Ruled the World." As Blow explains, "I just said, 'Hey, why don't I do one of those records?' "