When it formed in 1997, Dark Star Orchestra set itself a Herculean task that few cover bands have ever attempted or would ever attempt.

Actually, it was more of a Jerrygarcian task: The band decided that it wasn’t enough just to perform the music of the Grateful Dead. They would recreate specific shows to exacting specifications.

Rob Koritz is one of the band’s two drummers. Koritz assays the role of Mickey Hart in performances. Dino English channels Bill Kreutzmann.

In a phone interview, Koritz said that portraying Hart came naturally to him, because he was a fan. But Koritz portraying Hart is not the same thing as Koritz being himself.

“Mickey Hart was a big influence on my playing,” Koritz said. “Having said that, Stewart Copeland was also a huge influence on my playing. He used a bunch of splash cymbals. I can’t go up there and put a bunch of splash cymbals on my kit in Dark Star because that’s not very Mickey Hart.”

When he improvises in the band, Koritz has to improvise as Hart to a certain extent.

“I am improvising in my own voice,” he said. ”But there are definite parameters I have to stay within when I am improvising in order to keep the show authentic.”

Koritz is not one of the band’s original members. He said he joined “around show number 150.”

At the time, he said, he was still figuring out what sort of musician he wanted to be and thought the Dark Star gig would be a good temp job.

“I thought, ‘Yeah, this will be fun for two or three years,’” Koritz said. “I really did think it would be two or there years. My tenth day in the band, we were playing the Fillmore in San Francisco and we sold it out. I was like, ‘What is going on?’”

Koritz insists that no one in the band at the time had expectations that extended into the 21st century.

“If you would have said to me 20 years ago that we’d still be going strong in 20 years, I would have said, ‘You’re wrong,’” he said. “And we’re just getting bigger. We played Red Rocks this year for the first time. It took 20 years to get there and we sold it out.”

Dark Star Orchestra came into existence because a bunch of musicians wanted to play some music they loved, Koritz said.

“We didn’t know what was going happen,” he said.

One of the more improbable things that ended up happening is that former and current members of the Grateful Dead and its direct successors performed with the band.

One-time Grateful Dead vocalist Donna Jean Godchaux joined Dark Star Orchestra for its Red Rocks show, Koritz said. Bob Weir and Phil Lesh have also performed with the band, and Koritz has joined the Mickey Hart Band on stage.

At first, Koritz’ goal was to play music that would impress fellow fans. “I wanted their seal of approval,” he said.

But that goal has evolved.

“Now that’s still important to me,” he said. “It took me time to realize, however, something that is even more important to me: turning on these young kids who never saw the Grateful Dead, who never saw Jerry Garcia. Turning them on to an amazing repertoire of music that they might not otherwise be able to hear.”

Many of the band’s most ardent fans are people who were born after Garcia died, Koritz said.

Of course, Dead & Company (one of the Grateful Dead’s many post-Garcia incarnations) continues to tour, although not as fervently as its progenitor.

“But we’re a little more accessible,” Koritz said. “We’re out there a little more often, we’re coming to smaller towns, we’re less expensive, and we’re playing the music the way that it was played.”

Koritz said it thrills him to look down in a crowd and see multigenerational clumps of fans.

“Grandpa saw the Dead in the sixties, dad saw the Dead in the eighties, and the grandson never got a chance to see the Dead,” he said. “And they’re all singing and dancing along.”

A few years back, Dark Star Orchestra surpassed the number of live shows performed by the Grateful Dead.

It was hard to get too excited, Koritz said.

“To me, all the means is that I am on the road a lot,” he said.

Koritz is the father of two young children and leaving his family in St. Louis to go on the road is one of those trade-offs that will never feel comfortable.

“It’s hard on me, it’s hard on my kids, it’s hard on my wife,” he said. “That’s the occupational hazard, if you will.”

Koritz portraying Koritz.