SugarlandSugarland's Jennifer Nettles and Kristian Bush have been hard at work back in the studio putting the finishing touches on their fourth studio album, tentatively titled 'The Incredible Machine.' While no release date is scheduled yet for the project, Jennifer tells Billboard she hopes it will be sometime this fall.

Since the release of their 'Love on the Inside' album in 2008, the duo have been concentrating on building up a solid catalog of songs for the new album. "This time we wanted to be lean and clean with it and make conscious choices going into it," Jennifer explains. "If we felt like one wasn't working, we didn't finish it. From a writing standpoint, we've already been able to grow. And for me as a singer, you want to evolve. You paint with a lot of emotional colors, and you don't want to sing the same thing or sing the same way.

"Not only is it diverse within the context of these songs, but it's diverse compared to what we've done in the past," she continues. "Obviously it's me, [but] I really enjoyed exploring other parts of my voice -- the deeper, richer, more gravely parts of my voice."

Most of the details on the album are still being kept under wraps, but Jennifer says fans can expect a fun, upbeat record this go around. "We didn't make it ballad heavy, though we do enjoy those moments of poignancy," she says. "The arrangements use different choices of instrumentation. I don't know if there's even a mandolin on this record.

Sugarland are gearing up to hit the road on their U.S. tour, which kicks off at Primm, Nevada's Star of the Desert Arena on April 23.

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