RALEIGH — In 1990, Sam Bush, Del McCoury, Tony Rice, Bela Fleck and Jerry Douglas were the biggest names in bluegrass.

Today, they still are, and they’ll be playing together on one stage for the first time Friday at the Wide Open Bluegrass festival. Allison Krauss was scheduled to play with the group but canceled last week due to illness.

Craig Ferguson, co-producer for the festival, which will wrap up the International Bluegrass Music Association’s conference this week, assembled this group because the members were winners of the IBMA’s very first round of awards in 1990.

That, and because the “Epic Collaboration,” as the event is billed on posters and programs, is a dream team of performers known for respecting traditional bluegrass even as they push its boundaries.

“If you look at each of those artists individually, it’s difficult to imagine a more creative collection of artists of any genre, ever,” said Ferguson, who also produces well-known bluegrass festivals including Telluride Bluegrass and Rocky Grass in Colorado.

“You talk about ‘wide open bluegrass,’” he said, “one of the efforts here is to make a nod to the various other forms of music that have either been influenced by bluegrass or that bluegrass artists have danced off into, whether permanently or temporarily.”

‘A jam thing’

Banjo player Bela Fleck, for example, played a concert with the N.C. Symphony on Tuesday, Ferguson said, and will join fellow modern bluegrass greats for the Epic Collaboration Friday. The transition is likely to be seamless.

“Playing bluegrass music in a jam thing is something they’ve all done since they were about 14,” Ferguson said of the collaboration artists. “They’ll sit down and look each other in the eye and say, ‘Let’s play an old Bill Monroe tune, whaddya say?’”

But while bluegrass classics will likely find a home in the set list, there may also be some surprises, said Bush, four-time IBMA award winner on mandolin, co-founder of New Grass Revival and a bluegrass festival fixture.

“The common ground here is bluegrass music,” he said. “No matter how progressive that we have all played or can play, one thing I’m feeling confident about is that we will let bluegrass be our guide.”

Flexing different muscles

Bush said he’s looking forward to flexing some different musical muscles as part of this group, rather than fronting his own Sam Bush Band, and watching his peers do the same.

Stuart Duncan, fiddle player of the year in 1990, had a scheduling conflict for Friday’s show. (The other departure from the 1990 award-winner lineup is on bass: Mark Schatz, who won the first of his two IBMA awards in 1994, replaces Roy Huskey Jr., who died in 1997.)

“We all lead our ensembles that we play in,” Bush said. “I think it’s a welcome, fun thing for all of us to be able to relax, and when it’s your turn, then you’ll step up there and take the lead. But on the other hand, it’s great to be able to be in a backing situation for our friends.”

The artists, many of whom have played with each other but who haven’t all been on the same stage at the same time before, are likely to have just as much fun as the audience will, Ferguson said.

“I think all these guys are going to get a couple songs in and just have the time of their lives,” he said.