ATHENS, Ga. -- On the ground floor of a nondescript building, a few blocks from the University of Georgia campus here, sits a little room stuffed with instruments and decorated with Christmas lights, lava lamps, old concert posters and tacked-up 45s.

R.E.M. started rehearsing in this space in 1985, and it looks as if nothing has changed.

This is a place to work not hang out, and work is what Michael Stipe, Peter Buck and Mike Mills were doing on this March afternoon, blasting through 13 songs over the course of a few hours. It was their first day of rehearsal for the shows that would introduce their hard-charging new album, ''Accelerate'' (Warner Brothers), and they weren't exactly easing back onstage: later in the week they were headliners at the Langerado festival in Florida, followed by a performance at South by Southwest in Austin, Texas.

''We never do much rehearsal,'' Buck, 51, the band's guitarist, said over a ginger ale later at a dark, empty bar around the corner. ''Sometimes having that little edge of not feeling comfortable with the songs gives it a little bit of energy. Terror will do that.''

Despite spending 28 years together, at this moment a touch of fear is understandable for the trio. (The fourth member, the drummer, Bill Berry, left the band in 1997, after a brain aneurysm.) From its debut in 1981 until the mid-1990s R.E.M. was a definitive American rock band, but its sales and influence have steadily declined in the last decade. ''Accelerate'' is a very deliberate response to an internal crisis that Stipe, the group's singer, described as major, and that they all agreed almost broke up the band.

Buck said he had few commercial expectations and was much more concerned about making fans believe in the band again.

''Whatever we did on the last record didn't work,'' he said. ''I wasn't happy with it, and I don't think anyone else was. Michael tends to think that the longer you work on something, the better it can be. But it doesn't work that way for us. It just kept getting weirder and weirder and worse.''

''Around the Sun'' came after other R.E.M. albums -- ''Up'' (1998) and ''Reveal'' (2001) -- that also received lukewarm receptions and were more atmospheric and keyboard based than the music that established the group. The band had fallen from its place as one of the biggest acts in the world to being unable to reach gold-record status. This downturn followed a record-breaking $80 million contract the band signed with Warner Brothers in 1996, a move that recently made Blender magazine's list of the ''20 Biggest Record Company Screw-Ups of All Time.''

Stipe said the turmoil started as soon as Berry left the band. ''Any 5-year-old can figure out that with four people, you can have two very clear sides, but with three people, one person is always left out,'' he said, picking at his lunch in the front room of the rehearsal space. Soft-spoken and inquisitive, Stipe, 48, was nursing a shin injury from a recent go-kart accident, and a sore jaw where he had a wisdom tooth removed. ''The simple mathematics are that someone was always being ganged up on by the other two.''

Driving around Athens at nightfall Mills, 49, the group's bass player and keyboardist, agreed. ''Communication had broken down, and it had gotten repaired, and then it broke down again,'' he said. ''And then we said: 'OK, this can't go on. Either we're done, or we've got to refocus ourselves in some way.'''

After the tour that followed ''Around the Sun'' the band members gathered to determine their future.

''I said, 'Guys, I'm too old to spend nine months doing something I don't want to do, making work I'm not proud of,''' Buck said. ''We should try something different, or else you can do it without me.''

Stipe said: ''It was a very important moment for us. We decided to do something that was really raw, immediate, unrehearsed -- basically, gut and instinctual. And we chose the most obvious thing, which is to write really fast songs and record them in a really fast way.'' The aptly titled ''Accelerate'' is an album that should please R.E.M.'s old fans. Recorded in a matter of weeks rather than months, with 11 songs totaling less than 35 minutes, it's a steady blast of short, sharp rockers, a breathless tumble of hooks and harmonies. The album is reminiscent of R.E.M. favorites like ''Lifes Rich Pageant'' and ''Document,'' from the mid-1980s era when the band managed the Olympian feat of being both cool and popular, but it avoids the feel of nostalgia.

''Another mistake would have been to try to do exactly what we used to do back in 1985 or '86,'' Buck said. ''Back then we actually didn't record as live as this one is.''

Stipe's signature obscure lyrics are more focused and penetrating on ''Accelerate.'' In conversation Stipe, who has devoted as much attention to activism as to performing in recent years, retained his mysterious aura, veering from pragmatic political analysis to elaborate science-fiction metaphors and offhanded remarks about his depressions and insecurities. (He can also be pretty funny. When recent comments he made to Spin magazine about his life as an out gay man were widely discussed in the news media, he responded with a video statement on People.com, announcing that his band mates were finally coming out as heterosexuals.)

As always, his personality spills into the lyrics, which alternate between lamenting the state of American leadership (''The business-first flat earthers licking their wounds/The verdict is dire, the country's in ruins'') and exploring the evocative visions, taken directly from his dreams, that have long informed his writing.

R.E.M. is even promoting ''Accelerate'' with the energy of a young band, using strategies like posting a series of 90 one-minute video clips on the group's Web site, remhq.com. The official premiere of ''Accelerate'' will take place on Facebook.

''R.E.M. have been pretty savvy about the new music distribution model,'' said Scott Lapatine, founder and editor in chief of the music blog Stereogum.com. (Last year Stereogum assembled a tribute album commemorating the 15th anniversary of R.E.M.'s ''Automatic for the People.'')

Buck bristles a bit that ''Accelerate'' is being widely greeted as a comeback album. ''I don't feel like this is a return to form so much as this is the level we work at generally,'' he said. ''Of the 14 records we've made, I think 12 of them are pretty close to this.''

A return to R.E.M.'s classic sound may not be enough to attract new listeners. Aaron Axelsen, music director of Live 105 in San Francisco, said his station played ''Supernatural Superserious,'' the first single from ''Accelerate,'' about 50 times before dropping it from rotation. He described the reaction it received as ''polarizing'' for his modern rock audience. ''We were hoping it would bridge the gap to our younger, alternative listeners, but to a lot of them R.E.M. is their dad's band.''