When R.E.M. played St. Petersburg's old Bayfront Center in 1985, Mike Mills wasn't sure how he saw himself as a songsmith.
"I can tell you that the word composer probably never crossed my mind," the group's bassist — and, along with guitarist Peter Buck, one of its primary songwriters — said in a recent phone interview. "We were just trying to write rock songs. But I will say that Peter and I both felt very strongly that songs were the most important part of a rock band. If you didn't have great songs, it didn't matter how much talent you had."
That adherence to melody has carried over into Mills' latest project: Concerto for Violin, Rock Band and String Orchestra, a classical collaboration with celebrated violinist Robert McDuffie. Released Oct. 14, it's the focus of a new tour that this week brings Mills, McDuffie, a 15-piece string orchestra and four-piece rock band to the Mahaffey Theater, the same (albeit renamed) stage R.E.M. rocked 30 years ago.
It's been five years since the alternative rock icons broke up on good terms after 31 hugely influential years. Mills has busied himself with other gigs — his casual indie rock supergroup the Baseball Project has twice toured through Tampa — but Concerto is by far his most ambitious solo project. And it might catch some longtime fans by surprise.
R.E.M. was never very open about its songwriting process — Mills, Buck or drummer Bill Berry would typically compose the music, and singer Michael Stipe would add lyrics, but every song was credited to every member. That made it tough to suss out Mills' specific contributions beyond his driving basslines and high, harmonic tenor.
"The sharing of the songwriting credits for R.E.M. was the best idea we ever had," he said. "A lot of the money comes from songwriting publishing, and that's one of the first things that breaks up a band, is one guy getting more money than somebody else."
Mills had some experience with strings during his R.E.M. years — he wrote the string parts for Losing My Religion, for example, and learned to bow a double bass for 2008's Accelerate — but never harbored an ambition to go classical. "The precision required for a fretless instrument, to hit the right note, is just more work than I ever care to put into anything," he said.
It was McDuffie, a childhood friend who founded the Robert McDuffie Center for Strings at Mercer University, who encouraged Mills to write an original piece for strings. McDuffie's only request: that the concert include a movement devoted to the dreamy piano number Nightswimming, a 1992 R.E.M. hit written by Mills.
"Bobby and I have played that song together a few times before we ever had the idea of the concerto," Mills said. "It works very well in the context."
Nightswimming hails from one of R.E.M.'s most creatively fertile periods, which began 25 years ago with Out of Time. In November, that landmark album will receive a deluxe anniversary re-release, with plenty of live versions, rarities and demos that offer "an idea of how songs progress from their start to what they sound like on the record," Mills said. "Some of them are indeed very different."
The process of re-evaluating Out of Time, with its diverse instrumentation and broader sonic palette, gave Mills a new appreciation for the album.
"I don't listen to R.E.M. stuff for pleasure because I'm too critical and analytical about it," he said. "I listened to Out of Time about five or 10 years ago, and I was like, 'Eh, I don't know if I like it all that much.' I liked it, but I didn't know how good it was. But in listening to it for this re-release, I said, this is actually really good. It holds up a lot better than I thought it did."
Mills and McDuffie's Concerto feels like a rock album in places, with loud guitars and upbeat rhythms that Mills hopes will prove to fans "that the walls between classical and rock are thinner than you think." He hopes Friday's performance, the second stop on a 14-city fall tour, will "remove the stilted nature of a classical concert, and make this more of a fun show."
"Yes, there are movements, and there will be time between movements, for no other reason than I change instruments, so I have to get from one place to the next. But what we're trying to do is have the audience not feel like they have to be quiet. We want to approach this more like a jazz show or a rock show from the standpoint of audience participation. No one is expected to be silent. Please make noise. If you want to yell during somebody's solo, that's absolutely fine. If you want to applaud during movements, that's also fine."
And for R.E.M. fans, the concerto might help shed light on the songwriting Mills brought to the band.
"I don't need to be known as a great composer," he said. "That was never on my radar. Certainly, I think that if people see this concerto and like it, that will tell them something about what kind of songwriter I am. But for me, it's just about having fun and getting the audience to enjoy themselves."
Contact Jay Cridlin at email@example.com or (727) 893-8336. Follow @JayCridlin.