A Great Big World on Recording With Christina Aguilera: 'We've Never Heard Her Sound So Vulnerable'

Christina Aguilera Performing A Great Big World Split - H 2013
Tyler Golden/NBC; Getty Images

Christina Aguilera Performing A Great Big World Split - H 2013

The Voice has yet to find its Kelly Clarkson, Carrie Underwood or One Direction, but the show has proven a major springboard for musical duo A Great Big World. Consisting of vocalist Ian Axel and longtime writing partner Chad Vaccarino, the indie pop act took the stage with Voice coach Christina Aguilera to premiere the duet "Say Something" on the Nov. 5 episode -- a subtle but emotional performance that pushed the ballad to debut at the top of the Billboard Digital Songs chart last week.

"Chad and I were just both heartbroken at the same time, and writing this song was our therapy," Axel told The Hollywood Reporter on the pink carpet of the Victoria’s Secret Fashion Show, where they performed the song on the runway. Vaccarino added, "We could not be happier with how [Aguilera] did, how the recording came out. It’s amazing."

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For established A Great Big World fans, the song isn’t new, as “Say Something” was previously released without Aguilera and was featured in a number on Fox’s reality competition So You Think You Can Dance. Aguilera’s team heard the track and contacted the duo to reintroduce a version of “Say Something” with the pop star. However, as seen on The Voice, the song doesn’t spotlight Aguilera’s signature runs or textured solos characteristic of her repertoire -- a decision that also surprised A Great Big World.

"We actually were thinking that she would take a verse and do all this belting stuff at the end, but she didn’t want to do that, she wanted to let the song just be," said Vaccarino of the collaboration, which doesn’t have the calculated climactic moment of other Aguilera tracks. "It makes you kind of feel the longing [of the song]."

Axel echoed, "She wanted to let it breathe and just be open, and we’ve never heard her sound so vulnerable. From what she’s told us, she’s in a different place in her life, and she only wants to take on projects that inspire her, so we’re super honored."

While the duo’s other songs have also been licensed on television numerous times -- their recent upbeat track "This Is The New Year" was included in Garry Marshall’s New Year’s Eve and covered in an episode of Glee -- they’ve been quietly developing a big project that’s eyeing another stage.

"We’re working on a musical -- I can’t say much about it, but we’ve been working on it for about a year, a couple producers and a writer approached us," said Vaccarino. "New York is the goal. It’s a long-term project, so we’re in the middle of it right now, and we have no idea when it’ll come out." Axel hinted that the project sounds "like our music on steroids."

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Until then, A Great Big World is hitting the West Coast for a handful of shows, while their Victoria’s Secret Fashion Show performance of "Say Something" -- without Aguilera -- airs Dec. 10 at 10 p.m. on CBS, also featuring performances by Taylor Swift, Fall Out Boy and Neon Jungle. Even though Axel sat behind a grand piano on the glittery runway, he admitted his anxieties, and strategy to conquer them, before the show.

"We didn’t rehearse with the girls, so I’m nervous because I feel like I’m gonna be distracted!" he said. "I don’t know! I feel like for the first half of the song, I’m gonna close my eyes, and then gradually open them, and then it’ll be okay."

Both the original "Say Something" and the chart-topping version with Aguilera will be included on A Great Big World’s full-length album, Is There Anybody Out There? due out Jan. 14 on Epic Records.

Missed the duo's stage debut with Aguilera on The Voice? Watch the muted, yet powerful, performance below:

What do you think of A Great Big World's "Say Something" collaboration with Aguilera? Sound off in the comments below.

Twitter: @cashleelee