It's a task even many masochists would balk at. Take the music of one of the most popular rock bands of all time — one with some legendarily (some would say insanely) devoted fans who plan much of their lives around attending concerts — and turn it into a symphony show.

A show that had better please the band's biggest purists while attracting a new audience. And keep a world-class symphony interested and engaged in the material.

"It does seem a little daunting if you think about it, doesn't it?" Brent Havens laughs.

So Havens does his best to focus on creating it instead. He never expected this career as an arranger and conductor of symphonic rock programs. After all, the job didn't really exist before he essentially created it. Now, he has six symphonic rock programs under his conductor's baton and the seventh, and arguably the most ambitious considering the depth of the catalog involved — The Music of The Who— is set for its world premiere Friday night, right here in Houston at Jones Hall.

The basics of Havens' symphonic rock shows sound simple enough, if a little strange to anyone who's not aware of the concept. It's about putting a bunch of rock musicians together with an orchestra (in this case, the Houston Symphony) and playing the classics of an iconic rock band or figure.

But if you spend any time around Havens and his cast of musicians, you quickly realize simple seldom enters the equation.

I watched the extended end of a rehearsal on Havens' last trip though Houston — for a The Music of Led Zeppelin, which was the very first rock symphony Havens created, one that he and his group have been performing since 1995 — and the attention to getting every detail right came through. It didn't matter that Havens had done scores and scores of these Zeppelin shows around the country over 15 years plus.

He still wanted this one to be perfect — or at least as close at it could get.

So he stayed on the stage a good half hour after the rehearsal's scheduled end, to make sure that the sound was just right, that his lead singer Randy Jackson captured the tone just right, that everything was right enough. Havens takes the responsibility of the music very seriously.

"You're playing some of the greatest rock songs in history," he says. "You have to do them justice."

If you don't, you'll hear about it. Fans on the mega stars' message boards will be cyber howling long into the night, deriding the guy who did their beloved heroes' music wrong. Or just not the way they expected. Or every song they wanted.

Sometimes, Havens himself goes onto the boards, to get a feel for the reaction of the fans who care most. Other times, he'll use the boards for research when he's figuring out how to score a show and putting everything together. He did that for The Who, knowing the sheer number of hits that Roger Daltrey, Pete Townshend, John Entwistle and Keith Moon churned out would make whittling it down into a show an immense challenge.

"Most times I don't identify myself," Havens tells CultureMap. "I want to see what the fans are talking about and what songs they think should be included without affecting that discussion. But sometimes I'll join in the discussion as me.

"Usually not when they're screaming about something though."

And when Havens does get it right? When even the most doubting true believer who is certain that no one but Zeppelin can play Zeppelin, that only Daltrey and Townshend can do The Who is converted? Well, he might get a headline like this recent one in the Fort Worth Star-Telegram, "Band makes Led Zeppelin tribute almost believable."

That's the peculiar life of the king of symphonic rock.

Symphony Savior?

The Music of The Who is part of the Houston Symphony's Summer in the City Series, which also includes other non-traditional Symphony performances like Bugs Bunny at the Symphony, Distant Worlds: Music from Final Fantasy and Lord of the Rings: The Fellowship of the Rings, a showing of the popular film with the score performed live by the Symphony. It all fits into Symphony executive director/CEO Mark Hanson's vision of attempting to draw new fans with concerts that remind no one of your grandfather's Symphony.

"When we do audience surveys, the overwhelming majority of people in the hall for our shows have never been to a symphony performance before," Havens says. "It brings people in to see these incredible symphony musicians and to experience this wonderful music environment, people who would never think of themselves as symphony people.

"Are you kidding me? It's the Houston Symphony. One of the very best in the world. You bring them in to see that and they're blown away. It gets them thinking that maybe, the symphony is for them."

Still, Havens is not naive enough to think that the classically-trained, relentlessly-schooled orchestras are delighted to see him come into their halls.

"I'm sure a lot of the symphony musicians are rolling their eyes, thinking, 'Oh great, here comes the rock guy,' " Havens says. "I'm sure some of them don't like it at all. But they're so great, so talented and so professional that when you give them a piece of music, they pick it up just like that."

Havens snaps his fingers. "They're wizards. And I think some of them do get a kick out of seeing what they can do with a piece of rock music. I know I do. Every time."

Havens is a regular (if often brief) visitor to Houston for these rock symphonies. He and the rock musicians he's selected sometimes fly in the day of a show and fly out the morning after. But he knows enough about Houston, to have fallen for what matters in the city to him most (the symphony). While putting together the score for The Who show, and projecting when he'd be ready to premiere it, his thoughts kept returning to Jones Hall.

"Why not have the world premiere in Houston?" Havens says. "You're not going to find a better symphony to perform it with. And they had an open date when we were looking to get started and were as into the idea as we were."

With his bushy beard and his low-key off-stage manner, Havens comes off more professorial than rocker. He sits on a orange couch in the empty lobby of Jones Hall for this interview, the first spot that can be found that doesn't have a musician sleeping on it before the show.

In between questions, he often has to answer his phone to deal with very specific ticket requests from the star of the Zeppelin show, Randy Jackson. His usual assistant/talent handler is off, leaving all the little things to Havens too.

"I'm used to a little chaos," he shrugs.

Havens is a movie and TV music scorer, figured he'd always be a movie and TV guy, dependent on the whims of directors and producers. Until this crazy idea of a rock symphony came along.

"I figured we'd get to do it once," Havens says. "That'd be a fun, little insane thing to try."

More than a decade later, Havens is still doing them. They're still crazy, still ridiculously daunting. But sometimes crazy rocks.

The Music of The Who has its world premiere Friday night at Jones Hall. Tickets range from $25-$85.