'The Sing-Off' Season 3 Champs Are Pentatonix (Video)

The Texas quintet takes the win over the theatrical collegiate group, the Dartmouth Aires.

The Sing-Off may not have received the same attention its NBC cohorts at The Voice or Fox newcomer The X Factor got this season. But in many ways, Season 3 has gone the farthest in redefining what a cappella could be and how it could be relevant in today's music landscape. Its finalists included a group with an electronica bend, another that fused the singing style with hip-hop, and an all-male collegiate group with a flare for theatrics.

The show opened with an ensemble performance of Michael Jackson's "The Way You Make Me Feel" highlighting the season's breakout solo stars: Dartmouth Aires' Michael, Pentatonix's Scott and Urban Method's Katie.

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Then, each group visited different charitable groups for meet and greets and a private performance. Pentatonix  met with some kids from the Trevor Project to share experiences of overcoming being bullied. They then followed the taped segment with a performance of David Guetta's "Without You." For their second performance, host Nick Lachey joined the group for a trip back to his boy band past with 98 Degrees' "Give Me Just One Night (Una Noche)." He kept up, though he felt the need to apologize for being a bit rusty when it came to the choreography.

“I didn’t really move that much even when I was a youngster, but certainly I haven’t done it that much lately,” Nick explains to THR after the show. “It’s hard to sing a cappella, much less do it while you’re moving. And tonight is proof. I was like, ‘Oh my God, what’s going on here?’ But, it was a blast and an honor for me to do that with them.”

Urban Method visited with people who are living with sickle cell disease. It's a cause that hits home for the group, since two of its members have family members with sickle cell. Then onstage, they performed a soaring rendition of the Gym Class Heroes' "Stereo Hearts." For the group's second performance, judge Sara Bareilles joined them on her own song "Gonna Get Over You" with a 50s sock-hop vibe to the choreography. And apparently, Nick wasn't the only one who had some difficulties with the dance steps.

“Just me and that choreography were not friends,” Sara explains after the show. “It took me a while. Urban Method was so sweet and so gracious. It was fun to share the stage with them.”

Dartmouth Aires visited patients who are rehabilitating from strokes. They then took the stage on the Meatloaf's "Let Me Sleep On It" for the live audience, with guest female vocalist from eliminated group, Delilah. For their second performance, judge Ben Folds joined them on his song "Not The Same." And in a nod to the show's ability to make a cappella accessible, they enlisted the audience in providing some of the harmony. Sarah knew the  words by heart, though I can't say the same for Sean.

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Is anyone ready to get the winners already? Uh, uh, not yet. The show has other tricks up its sleeve. First, its female talent came together on a silky version of Aretha Franklin's "You Make Me Feel Like (A Natural Woman)." The men then brought the energy level way up on Bruce Springsteen's "Born To Run." Finally, guest performer Smokey Robinson joined last week's eliminated group, Afro Blue, on his hit, "You've Really Got a Hold on Me." From what I picked up from the audience chatter afterward, there was a general concensus that Smokey still has it.

And finally, the three groups are brought on stage, and Lachey begins the process of eliminating the first group. And to the surprise of the audience, America's votes place the hip-hop/a cappella fusion group, Urban Method, in third place. It's a bit of a surprise since Dartmouth Aires was in last week's bottom two.

After reviewing the journey for each group up through Monday's finale, Lachey prepared the audience for the winning announcement. And the winner is... Pentatonix, the Arlington, Texas, quintet who were able to provide a sound just as full as many of their competitors with larger groups. They also brought a unique take on composition and an ability to replicate the sounds of electronic music with their inventive talent.

To their credit, the members of the second place group were good sports about the loss.

“To be perfectly honest, we didn’t know what the outcome would be,” Darmouth Aires’ Preston Suan tells THR after the show. "The other two groups that we were competing against were absolutely fantastic. It’s just such a great honor that we’re even mentioned in the same sentence with them. We had no expectations. We just wanted to do as well as we could.”

Were you happy with America's vote? Tell us in the comments section below.

Re-watch the winning moment below.

Email: Jethro.Nededog@thr.com; Twitter: @TheRealJethro