Sophomore stress

"Room on Fire," the second CD from the Strokes, comes out Tuesday. And one need look no further than the album's opening and closing lines for clues to how loaded this moment is. "I want to be forgotten" are the first words out of lead singer Julian Casablancas's mouth. "I'll be right back," he promises at the end.

If Casablancas's outlook seems hopelessly splayed, consider the Strokes' short, luminous history. Early in 2001, the band released a three-song demo as an EP called "The Modern Age." That trio of sharp tunes sparked a bidding war -- RCA won -- and a general consensus midway through a year saturated with slick pop and faux grunge that the Strokes were the closest thing to rock 'n' roll saviors anyone had heard in years.

A few months later the band released its major label debut, "Is This It" -- 11 febrile, New Wave nuggets that lashed New York punk to classic pop with the sort of zealous disaffection downtown scenes are built on.

The young quintet was catapulted to momentarily mythic status.

It's two years later, the day before the Strokes leave on a tour to support "Room on Fire," which brings the band to Lowell's Tsongas Arena on Friday. Casablancas is sitting in a booth at Joe Junior's, a nondescript coffee shop a few blocks from his apartment in the East Village.

Dust flecks are stuck in the singer's hair, nightclub wristbands choke his arm, and his teeth need cleaning. Donna Summer's "On the Radio" is playing, a surreal bit of poetic subtext to the musician's state of mind.

Casablancas is innately testy, nervous as hell, and struggling to be cordial. Suffice it to say there's a lot riding on "Room on Fire." Or not, depending on whether you're courting stardom or greatness.

"We want to get better," Casa-

blancas explains. "That's the key. There are amazing things to be done, and the fantasy is actually doing them. All the other stuff that comes with it is great, but the whole fame thing is all cluttered in with the creative world. It's so easy to lose it. There are so many traps. The main trap people fall into is copying yourself." "Room on Fire" sounds like the Strokes but more. World-wearier vocals. Spikier guitars. That motorized backbeat with a bigger, faster engine. Of course it's a crooked (and thoroughly subjective) line between falling back on the familiar and affirming your identity, so let's just say that if the rock cognoscenti were hoping for either revelation or revolution on "Room on Fire," they'll be disappointed.

Anyone hoping for another stellar batch of Strokes songs, however, will be thrilled.

The album may clock in at a blunt 33 minutes, but more effort and anxiety went into that half-hour than the Strokes' sleepy-eyed, swaggering image would suggest.

Casablancas is a serious and exacting musician whose privileged youth (he's the 25-year-old son of modeling kingpin John Casablancas) and enthusiasm for cocktails have threatened to eclipse the thing that got him noticed in the first place.

A typical day often involves 10 hours in the Strokes' rehearsal space. The band's marathon recording schedule kept members in the studio from roughly 2 p.m. to 4 a.m. for much of the spring. And it's not just the songs. The Strokes agonized over the length of the gaps between them -- the tip of an iceberg-size obsession with building the perfect rock 'n' roll beast. "We're very very ambitious, and we work well under pressure," says guitarist Albert Hammond Jr., the son of songwriter Albert ("It Never Rains in Southern California") Hammond. He and Casablancas, who met at a tony Swiss boarding school when they were 13, are roommates. They formed the Strokes in 1998 with guitarist Nick Valensi, drummer Fabrizio Moretti, and bassist Nikolai Fraiture. If Casablancas is the band's undisputed leader, Hammond -- a mop-topped, baby-faced 23-year-old -- is the band's de facto ambassador to the world, for reasons that become clear over a sushi dinner.

"I think the record is pretty but really dark," he says. "Yeah, a little tougher. Like some things needed to come out so we could get somewhere else later."

Hammond, the amiable, smiling foil to Casablancas's coiled skeptic, likes to chart the band's progress in baby steps -- "Let's be able to finish a song, let's be able to have a bunch of songs, let's play a show, let's make it to the [hip New York City music club] Mercury Lounge."

The new album fits right into such a pragmatic and efficiently realized arc. The Strokes reunited with "Is This It" producer Gordon Raphael, but not until after they tested the waters with Nigel Godrich, the elite Brit best known for his work with Radiohead. Three weeks in with Godrich at the helm, the Strokes knew it wouldn't work. "We had a great time. But we're very involved, and Nigel is more of a headstrong producer," says Hammond. "We want it to sound right now. Not later, not in the mix. I think if we had six months to record and it was our fourth record and we wanted to try something new, it might be great to make a record with him."

Raphael, by contrast, functions as the Strokes' consecutive translator. According to Hammond, he has no ego, isn't happy until the band is smiling, and is fluent in the Strokes' musical language, which favors a rather personal catalog of imagery over technical terms.

"If you tell him it sounds too trebly, that's nonsense, a waste of time," says Casablancas. "But if you say `make it sound like an angry ogre cuddling a small cub,' he'll do two or three things and it's perfect."

You can't buy a relationship like that. When Casablancas first met Raphael, the singer played him albums by the Velvet Underground, old R.E.M., and John Lennon. Raphael, says Casablancas, "just got it."

Neither can you hire someone whose role is so vague and important that he's credited on the new album as the band sensei. No one can say exactly what J.P. Bowersock does. But he's always there, and his contribution is incalculable.

"J.P. has knowledge about everything in life," says Hammond. "You can talk to him about your girlfriend and about how jazz started and the fights in the band. He taught me how to play guitar, and he tells us when it's a great take. In the studio, where everything is so fragile already, it's really nice to have people like that who are just there because they love you and love what you're doing."

The band has cultivated a warm, tightly guarded circle of insiders, among them Moretti's girlfriend, Drew Barrymore, and Valensi's current squeeze, actress Amanda de Cadenet. Beyond that there are -- perhaps not surprisingly -- trust issues, the kind that deepen in direct proportion to the coolness of your band.

Which explains, in part, why the Strokes spend so much time together. But the insulation works both ways: protecting the band from a world of hangers-on and nurturing the sort of work ethic that begets greatness. Plus, hanging out is as much a part of being the Strokes as playing music.

"Once you lose that, it's just this weird job," says Hammond.

"Bands don't break up for nothing," notes Casablancas, whose own band toured to the point of physical and mental exhaustion in 2001 and 2002. Mistakes have been made in the Strokes' never-ending quest to be bigger, better, faster, more. Touring the world before their first album was out may have been one of them. But they have something to prove. And lessons have been learned. Case in point: "Room on Fire" -- a brief, smoldering burst of rock tunes that accomplishes the daunting task of justifying the hype. The future must look bright.

"I think about what I can do now so when the future happens I'm not kicking myself," says Casablancas. "If we start writing songs now and we can get to the point where we can make a third record that's hopefully better than the second and we keep it in mind that that's our goal, we'll be in a pretty happy spot. Regardless of whether people say things about us or don't mention us at all."

Joan Anderman can be reached at anderman@globe.com.