There's talking, laughing and the clinking of beer bottles. Suddenly, the sound of four perfectly tuned voices echo off the walls of the Paris Métro. Inside the train, four young men grin at one another and strike up a beat on a metal pole. As the clinking intertwines with clapping, they break out once again in harmony. The faces of average French citizens stuck on the subway in the wee hours of the night slowly morph from flabbergasted confusion into an enchanted look of euphoria.

The performance is like witnessing world diplomacy through song. The train slows to a stop, the doors part and whistling applause escorts the men out onto the platform. The foursome giggle as if they're immensely surprised with the music they've just created.

As cheesy as this video clip sounds, these exuberant young men are at the forefront of indie alternative music's new wave.

Welcome to Yeasayer, people.

On their debut album, All Hour Cymbals, the band's self-proclaimed "Middle-Eastern-psych-snap-gospel" sound is a collage of chimes, occasional a cappella harmonies, African and Indian beats pounding away in the background, and wispy synthesizer layers. Psych-snap-gospel hardly begins to describe it.

Pronounced "yay-sayer," the band is comprised of a cacophony of musical talents: Anand Wilder, Ira Wolf Tuton, Chris Keating and Luke Fasano. Wilder and Keating became friends during high school in Baltimore, Md. In 2004, the duo reconnected in Brooklyn and began playing music. A year later, Tuton joined as the bass player, and in the summer of 2006, Fasano's drums formed the backbone of the group.

Yeasayer are only one of recent Brooklyn imports to the popular music scene. Along with bands like Vampire Weekend, MGMT and Animal Collective, they are slowly transitioning from underground experimentation to hipster playlists to guesting on such mainstream fare as Late Night with Conan O'Brien and MTV.

Commercialism may be the name of the game in Manhattan, but Brooklyn gives artistic innovation a new stomping ground, heralding the rebirth of the broke and statusless musical genius.

While Yeasayer may find their home and inspiration among the crop of new bands like A Place to Bury Strangers and the Muggabears, their results sound far different. Where A Place to Bury Strangers pair lazy vocals with frenetic, pulsating drumbeats, Yeasayer lean toward the mystical side of the spectrum, kneading the drumbeats and guitar into wispier rhythms. The Muggabears, who classify themselves as "emotronic," are just that: a little more pop and a little more angst, like a grunge version of the Australian band Jet. Yeasayer hit the middle mark with ease, each track of All Hour Cymbals more expansive and multifaceted than the last. They are relatable. Listenable.

"Beautiful" is the one word that crops up again and again with reference to Yeasayer in music blogs and review sites. Their lyrics are beautiful, the sounds are beautiful, the sentiment is almost too beautiful to handle. What exactly are these four guys—all hailing from different areas of the East Coast but all living in Brooklyn now—doing to evoke such strong reactions? The secret lies in the content. Not in the trippy melodies, and not in the Phil-Collins-circa-1980s vocals in tracks like "Sunrise," but in the nature with which they tackle some startlingly pessimistic subject matter. In their single "2080," which launched their introduction into the mainstream, lead vocalist and keyboardist Chris Keating sings, "I can't sleep when I think about the times we're livin' in / I can't sleep when I think about the future I was born into." Such a harsh take on issues facing the world today was in part motivation for the band's unique name.

"The name 'Yeasayer' seemed positive," Keating recently told New York Noise, an indie and underground music television station. "You know, we thought, 'If we have a positive name, then we can kinda go ahead and talk about the dark stuff.'"

In a Top 40–driven musical market, Yeasayer have managed to create something new, which is normally thought to be an increasingly futile goal for new musicians. The bands coming out of Brooklyn are turning alternative indie music on its head, and Yeasayer are right there, bringing in that Middle-Eastern-psych-snap-gospel. Right on.

Yeasayer appear July 19 at San Francisco's Download Festival. www.downloadfestival.com.

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