Even though Underoath [ tickets ] has sold more than a million albums, singer/guitarist Spencer Chamberlain is still shocked when his Christian metal band finds success.

"I'm always surprised when [our music sells], especially with the way kids just steal albums off the Internet now and no one really buys anything," said Chamberlain during a recent phone interview from Philadelphia. "I was really surprised in this day and age. I didn't expect it to do anything."

He is referring to Underoath's latest album, "Lost in the Sound of Separation," a collection that debuted at No. 8 on The Billboard 200 chart after selling 56,246 copies following its Sept. 2 release.

Chamberlain shouldn't be surprised. Underoath's 2006 album, "Define the Great Line," bowed at No. 2 on The Billboard 200 chart, marking the highest chart debut for a Tooth & Nail artist. On top of that, Underoath earned a Grammy nomination for "Best Short Form Music Video" for the album's lead single, "Writing on the Walls."

Although Underoath found success with previous efforts, "Lost in the Sound of Separation" is a marked departure for the band. In a separate interview this summer in Phoenix, bassist Grant Brandall said Underoath--which also includes drummer/vocalist Aaron Gillespie, lead guitarist Tim McTague, rhythm guitarist James Smith and keyboardist Christopher Dudley--pushed itself "to the limit." He explained that the guys are at a spot where they're comfortable enough with their instruments and themselves to try different things.

"We tried to go for more of an organic feel, not so polished," said Brandall, whose right arm is adorned with an elaborate tattoo representing the Bible's Jonah and the Whale. "We kept in the weird noises and squeaks when you play the guitar.

"It has more of a live feel. We have some cello on the actual album. There's a slide guitar. We've never done that before. One thing we did that we've never done before is there are no double vocals. A lot of times you'll have a chorus and Aaron our drummer will sing and we'll add another layer of him singing on top of it. Everything is either him or it's two people. It's him and Spencer, our singer. Then, if it's harmony, it's him and Spencer, so it sounds live. I think it came out really cool. I was listening to it at home after recording it and, hearing the last record we did and this one, I like the vocals so much better on this one. It sounds more real. It's not polished."

The songwriting process for "Lost in the Sound of Separation" was similar to Underoath's previous albums. Chamberlain said he penned the lyrics and the rest of the band members wrote their own parts. Brandall concurred.

"Usually Timmy, our guitar player, will have some riffs and bring them to practice," Brandall said. "Him and our drummer Aaron will rip through them, and bring them to the group at practice. Everyone gives their input. Everyone has their say. Everyone ends up writing their own part and adding their own touch to it. If one person doesn't like it, then it goes. All six of us have to be on the same page. We go to the studio after two years of writing and what we're going in the studio with is exactly what goes down."

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