What rappers such as Kanye West and Jay-Z do with syncopated rhymes and rhythms, the Portland Cello Project bangs out with strings and bows. And they don't stop there. Pop tunes from Britney Spears' "Toxic" to Justin Timberlake's "What Goes Around" also bring cheer to their fans.

"It just seemed like the natural thing," Doug Jenkins, a founding member of the band told Reuters. "We began stumbling around trying to find the most fun or confusing songs to perform on the cello to play with people's perceptions."

Now on national tour to promote their new album "Homage," which was released this past Tuesday, the collective aims to challenge the conventions of their instrumental classification.

Portland Cello Project formed six years ago as a loose group of cellists who kept bumping into each other around town and decided it only made sense to hang out, drink beer and jam. Eclectic in background and taste, some brought indie rock sensibilities to the table, others clung to jazz and folk.

After playing in each other's living rooms, they went live in their first public gig in 2006 at a local lounge. Rather than perform something expected like Beethoven - they did what any good-natured Portlander would do - they opted for Spears and over time became a local sensation.

Seizing on their celebrity, the crew of about 10-20 rotating members then branched into hip-hop, making symphonic arrangements out of songs like West's "All of the Lights," Jay-Z and West's collaborative "H.A.M" and Lil Wayne's "Lollipop."

"Hip-hop right now is the most vibrant American cultural art form," said Jenkins. "Like it or not, it sells a lot of records, and is extremely influential. It was also a challenge because these songs aren't obvious musical compositions. They have really fascinating productions behind them."

"Homage" mixes tracks from West and other performers like Talib Kweli and Outkast with the work of contemporary classical composers in a compilation Jenkins describes as "court and courtiers" music.

Although the band has been successful in many adaptations, not every bass line translates well. Some tracks, like 50 Cent's "In Da Club," contain hooks, bridges, and other parts too complicated or mismatched for classical.

SHOCK AND AWE

Portland Cello Project's music doesn't hinge merely on inventive renditions of others' tunes, but also in their contradictory play lists that keep audiences guessing and, even at times, listening with a sense of awe.

"The juxtaposition of playing (heavy metal band) Pantera at a live show, and following it immediately with a Bach cantata is really funny," Jenkins remarked. "There's that feeling that Grandma is wondering what's happening on stage and then suddenly she's comfortable again."

Their sometimes three-hour live shows have included guest appearances by many of their contemporary muses, including The Dandy Warhols, members of The Decemberists, Peter Yarrow of Peter, Paul and Mary, and Suicidal Tendencies.

Though they have yet to feature a rapper alongside them on stage, Jay-Z recently gave the band a nod on his Facebook page and blog, Life + Times. And Jenkins hopes for a future collaboration, saying that joining forces with a hip-hop icon would offer the unassuming Portlanders a legitimacy they seek.

"On tour, we're playing hip-hop music, but not giving a real hip-hop experience. (The crowd) seems more like indie rock shows, where there's kind of a divide in the audience as to whether the music is cool enough ... But to bring a hip-hop artist on stage, it's just automatically you love it."

There's always a Tupac hologram.

Beyond unusual selections, the group aims to display the dynamism of the cello, an instrument Jenkins feels often gets tagged as an accompaniment.

"Historically, there's a longstanding misconception that the cello can't do that much; that it can only play low bass notes," he comments. "But we can go much higher, right into violin ranges. It's a really versatile instrument."

On the road, they bring only wind and brass instrument players as compliments to their urbanized concerto. No other strings allowed.

And reception has been positive.

"There are so many nights where we're playing in a bar...and all of a sudden after 30 seconds, you can hear a pin drop even though everyone's drunk ... That feels like success."

(Reporting By Courtney Garcia; Editing by Bob Tourtellotte)

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