We've been through enough Britneys, 'N Syncs and Lil Bow Wows that you probably have to tax your brain to recall just how weird the summer of '97 felt.

You're forgiven if you can't quite conjure the old sensation; seven years, after all, is several eons in the MTV-paced cycle of pop culture. But try to remember the first time you heard "MMMBop" on the radio, or the second time you heard it and could already hum along, or the moment you learned that Hanson was a trio of young brothers whose drummer was 11 years old.

As with the out-of-the-"Blue" success enjoyed a few months earlier by LeAnn Rimes, who stormed the charts at a tender 13, it was easy to chalk up the brothers Hanson as a one-shot novelty - a quick, quirky phenomenon offering light relief among the Pearl Jams, Puff Daddys and other heavy hitters.

In 1997, a teenage cameo on the pop charts was curious and cute. What few realized then, as the peppy "MMMBop" lit up America's radios, is that Hanson was opening the floodgates to a phenomenon that would dominate popular music into the new millennium.

It was an onslaught of teen music now so familiar we take it for granted: featherweight pop made for young people, by young people. Seven years ago, it was a novelty. Today it's the way of the pop world.

For those irritated by today's lip-synced, airbrushed, choreographed state of affairs, the biggest frustration is what could have been. With the arrival of Gen Y, a new crop of young pop was inevitable. The disappointment is that Hanson, the one that got there first, was the last to do what it did: play rock 'n' roll.

Sure, "MMMBop" was chirpier than an Archies song. But it was rock. Guitars, drums, bass. The kids loved it, plenty of adults secretly loved it, and Hanson's mammoth success seemed to presage a promising next chapter for rock 'n' roll. The Beatles, after all, began as bubblegum, and look what they launched.

But it didn't happen. The same adolescent audience that swooned over Hanson soon tore down its Taylor posters and drifted to a decidedly un-rock 'n' roll world - the realm of Britney, Backstreet and 'N Sync, dominated by slick stage moves and faux-soul vocals digitized to death by studio wizards.

It's a long road from Hanson's soulful sunshine rock to Hilary Duff's manicured dance-pop.

Guitarist Isaac Hanson, the oldest of the brothers, is 23. His band has just released another album this year, "Underneath," a serving of power pop featuring collaborations with such underground rock savants as Matthew Sweet and Gregg Alexander. And while Hanson's core fan base never gave up, the rest of the world quit taking notice.

"Looking back, I take it with a grain of salt. But I took it with a grain of salt then, too," he says. "It comes and goes so quickly, and we knew that. You can never put too much significance into it. You just have to be yourself and make music you feel from your gut, and hopefully your audience will respond. The unfortunate thing is there are some people who never understood who we are."

As a unit, the trio has gotten tighter with time, Isaac says, with drummer Zac having grown into a muscular, agile pounder. "His backbeat over the years has only gotten deeper," says Isaac. "His pockets have gotten so deep, he can taste the lint."

The organic "Underneath" showcases that growth, both in songwriting and performance. But will people listen? Was Hanson doomed by its very success - or even more cruelly, by its association with groups whose music was truly trifling?

Isaac isn't interested in chatting about marketing science. He just maintains a single aim for his band - a goal he says was around long before Hanson helped kick off a revolution.

"In a phrase: I always hope it keeps getting better," he says. "When we were young guys, there was a certain thought process in some people's heads that, 'Oh, this is a novelty.' What's really important is that all we ever were was a band. And all we ever wanted to be was a band."