"One of the great things about being in a band is that you feel like you're in a gang," Eleanor Friedberger, one half of sibling duo the Fiery Furnaces tells Spinner. "You can make up a new persona when you're in a band. That is what is so cool about rock 'n' roll. But because Matthew and I are siblings we don't have that same sort of gang mentality. We're a family, which doesn't feel very cool, for lack of a better word."

Though there's a squeaky clean label usually associated with harmony-singing, toothy grin-flashing sibling acts, the Fiery Furnaces certainly don't fit that mold. The Friedbergers' eighth album, 'I'm Going Away,' encapsulates their love of Harry Nilsson, swamp blues, New Orleans boogie, Randy Newman and everything -- and anything -- 1970s. But Eleanor believes the band's music is challenged by its perceived image.

"When we began, Matt wanted to use a fake name," she says, "but I thought that was really wrong. But now I wish we had done that. Watching siblings is not as fun. It comes off as being precious or cute, which we get accused of being a lot. It's hard not being like that when you are a family act."

Never ones to adhere to style or repeat performances, the Friedbergers have exorcised various musical demons as the spirit moved them over the course of their eight albums. They jammed 2004's 'Blueberry Boat' with a rootless collection of rambling, near rock opera epics. The Friedbergers' grandmother, Olga Santos, joined them for 2005's 'Rehearsing My Choir,' warbling up a storm between Eleanor's hyper vocal syllables and Matthew's arcing analog synths. 2007's 'Widow City' rocks hard while retaining the band's penchant for wacky sounds and experimentation. Matthew, the group's principal songwriter, refuses to be straight-jacketed stylistically.

"We think ours is a traditional approach," he says. "You can be a special type of band like the Ramones and make the same record many times because you have a special 'message.' But more traditionally, bands are obligated to make different records each time. You have to justify your continued existence by changing. Now everyone wants to establish their brand. It's not that the bands in the old days were less commercially oriented or less bread-heads, it's just that fashions change. The commercial wisdom then was that you have to change. Three months ago you had a hit record; what do you have now? The kids don't want the same thing so you have to change to fill the coffers. We've had managers say 'It's not about broadening your fan base but giving the fans what they expect and giving it to them in a monetized fashion.' Now, that's not very pop now is it?"

A student of music history and music trends, Matthew even defends the much-maligned rock opera as a worthy vehicle for self expression. It's no surprise, given the instrumental outrageousness of some Fiery Furnaces music.

"We like the dramatic inventions of rock 'n' roll," he admits. "Traditionally, or at least since the Beatles, every rock record is an act in a continuing story that is the band. That's how people related to the Beatles. That's why '60s music was so powerful. It was a more effective imagination machine for fans than any two hour movie. With 'I'm Going Away' we wanted people to detach the songs and use them however they want in their lives. That's how people have always used commercial music and art music songs. People get mad about rock operas because that short circuits their ability to do that. But you can listen to the Who's 'Pinball Wizard' as a song in 'Tommy,' the rock opera, or as a song about an underdog.

"We played at Berklee School of Music for all these serious kids who want to get into the music industry," he adds. "It's so funny. Things only become a fit subject for academia when they're over and dead. So now that the music industry is over and dead you can get a degree in it from Berklee or Villanova. They have classes on how to run a street team when you're an intern at Dave Matthews' manager's company."

Ever flowing with new ideas and projects, the Fiery Furnaces are about to launch a fall tour in support of 'I'm Going Away.' Plans are also in the works for the upcoming 'Silent Record,' a Fiery Furnaces songbook and a covers album featuring Eleanor and Matthew's solo renditions of the Fiery Furnaces' catalog. Speaking of solo renditions, surely the Friedbergers clash like any normal brother and sister?

"The biggest plus is that we know how to argue," she confirms. "A lot of bands end up resenting each other or breaking up because finally one day someone snaps and they tell you what they really think. Matt and I are honest with each other all the time. And if we say something that offends the other person it gets forgotten very quickly. In other bands if you suddenly scream at someone it could destroy the relationship. But we can scream at each other and there aren't the same repercussions."