It's not just that the conservatory-trained, alt-classical Portland Cello Project brazenly and astoundingly covers dozens of diverse artists such as Britney Spears, Jay-Z and Suicidal Tendencies - as well as all those expected Elgar and Haydn people. No, in 2008, the Portland, Oregon-based ensemble actually did a tour as the opening act for arch-guitar-weirdo Buckethead - and lived to tell about it!

"It was one of the strangest experiences of my life. It was our first tour, and no one knew what to expect but ? it wasn't THAT," says cellist Doug Jenkins, general manager and artistic director of the Project, who perform Sunday in New London's Hygienic Art Park. "We never got to meet Buckethead. Well, we kind of got to meet him. We communicated by notes through his tour manager, who called him 'Bucket.' And the tour manager would have a note in his hand and say, 'Hey, Bucket wants to know if you guys are having a good time.'"

Buckethead, of course, is the virtuoso guitarist who's as adept at metal shredding or Parliament-style funk as he is at creating some of the most lovely ambient soundscapes in the world. He also wears a Jason-style hockey mask and an upside down KFC bucket on his head.

"I did see him without the chicken bucket, but never without the mask," Jenkins says. "He'd show up about 15 minutes before his set and, yes, the mask would already be on."

If it's a gimmick, Buckethead is apparently serious about it. Similarly, the Portland Cello Project's devotion to odd and stylistically diverse arrangements started as a "wouldn't it be funny if ??" gimmick, too.

Jenkins says a group of cellists moved to Portland at roughly the same time about six years ago. Classical gigs being relatively scarce, each was playing in a variety of different musical genres. It occurred to them it might be fun to book a bar gig as a one-off thing, playing material that might run against type - hip-hop, Top 40 pop and movie themes being fairly obvious targets - and the idea took off.

Eventually, the PCP evolved a tripartite set of core principles: to take the cello to new audiences; to play music on the instrument you normally wouldn't hear; and to bridge musical communities and encourage new collaborations.

"I've always listened to a large variety of music and certainly classical," Jenkins says. "But to grow up in this era means you're exposed to a lot of different stuff. We started to get fascinated by the differences in contemporary music. The rhythms and structures presented interesting challenges in terms of arrangements."

The Project is comprised of a core group of cellists - Jenkins, Gideon Freudmann, Zoe Keating and Jenette Mackie - and a revolving list of other cellists, as well as lineups that increasingly rely on percussion, woodwinds and brass.

One of the first things the Project did was an arrangement of Britney Spears' "Toxic," which went over so well that they rapidly pushed into rap territory. Their version of Jay-Z's and Kanye West's "H*A*M" resonated enough with Jay-Z that he blogged about it, and a Youtube video of the PCP playing West's "All of the Lights" went viral.

With the increased attention, the Portland Cello Project became a genuine artistic entity and began to tour. They've released six albums and EPs including the brand-new "Homage" and 2009's "The Thao and Justin Power Sessions," the latter for the hip Kill Rock Stars indie label.

Of the Kill Rock Stars deal, Jenkins says, "Well, they're based in Portland, too, and it's just a wonderfully cool musical community where anything goes. We know those guys fairly well, and at some point we all said, 'Wouldn't it be funny if we did a record together?'

"That way, they could say they had a cello ensemble, and we could say we were on this really hip indie label. It worked out great. It was always supposed to be just a one-time thing, but we've been talking. It might actually happen again."

As the Project's profile continues to grow, new audiences see or hear the band and realize that, while there's obviously a touch of irony to what they're doing, there's also a great deal of creative adventure in tackling contemporary popular music from a classically trained perspective - and that part of the challenge is presenting the whole package to fans.

"We do a lot of set programming for each particular audience, because we play in a lot of different venues and for people with different expectations," Jenkins says. "We're obviously going to do Bach, but then we'll maybe hit them with Britney to keep them on their toes."

As for the classical community from whence they sprang, Jenkins says there's been surprising support.

"There was definitely a skeptical reaction at first. There still is - it's normal in this situation," Jenkins says. "But I can't remember any outright hostility. Our experience has been that, when most classical musicians or critics see what we're doing, they think it's funny. At the same time, we offer a different sort of visual. Most symphony performances have the intermediary focus on the conductor. There's a lot more direct communication between us and the audience, and that further helps us break down barriers."

IF YOU GO

Who: The Portland Cello Project

What: A collective of classically trained cellists who collaborate with other musicians on arrangements of material ranging from the expected classical repertoire to hip-hop, rock and pop.

When: 6 p.m. Sunday

Where: Hygienic Art Park, 79-83 Bank St., New London

How much: $8

For more information: (860) 443-8001, hygienic.org, portlandcelloproject.com