“The Sing-Off” concludes its third and longest season Monday (Nov. 28) on NBC, with a cappella groups the Dartmouth Aires, Pentatonix and Urban Method vying for the prize of $200,000 and a Sony Music recording contract.

Since the show has been on a few seasons, the judges all say the quality of the groups has gone up. That’s perhaps partly because they’ve been listening to what longtime judges Ben Folds and Shawn Stockman have been saying all along (and former judge Nicole Scherzinger, now on “The X Factor”).

If the show returns for a fourth season, perhaps future competitors will benefit from what new judge Sara Bareilles has been able to add.

All “The Sing-Off” judges are experienced performers in their own right. R&B singer Stockman is a member of the vocal group Boyz II Men, having begun his musical career at the age of eight with the Philadelphia Boys Choir & Chorale.

Standing backstage during production on the show, Stockman reflects what he loves about a cappella, which features only voices.

“It’s one of the only pure art forms left,” he tells Zap2it. “You can’t fake voices. When it’s live, it’s live. It’s real, and it’s organic. I don’t care who you are — and that’s the beauty of the show — you can be turning and surfing the channels, and you hear some of those beautiful voices, and you stop. That’s the beauty of the show. It’s real. This is reality.”

The-Sing-Off-Shawn-Stockman.jpgOften during singing competitions, judges will talk about pitch problems, saying that the performance sounded “pitchy.”

When you have no musical instruments to help you stay on pitch — and all the audience hears are voices — that can be a problem.

For Stockman, it’s all about breathing.

“It’s very simple in theory,” he says. “To sing, you need to breathe. You need oxygen. The less oxygen you have, the less likely you are to be on key. The more oxygen you push out, the more you breathe in … you need air to breathe to sing.

“That’s the very first thing I was taught at eight years old in the Philadelphia Boys Choir. We breathed for 15 minutes from the diaphragm. Seriously, it was like learning to extend from your diaphragm and breathe like that. The diaphragm holds more air. Your stomach expands, and it comes from your bellow.”

Of course, that can be a bit tough when you’re trying to suck it in and look good onstage.

“It’s hard to do when you’re singing and dancing, but you tend to get used to it,” Stockman says. “It’s not always perfect, but when you get a chance to do it and do it right, when you take that right breath, you hear how nice it sounds.”

Asked which singer of his generation has the best voice, Stockman hesitates.

“That’s a tough one,” he says. “Because, there are great singers, but the songs, a lot of times, these days … it’s really about the song. It’s a shame that a lot of these great singers don’t have songs that cater to the voice. It’s a lot of fluff.”

Here’s Stockman doing “If U Were a Boy,” so you can judge the results of his technique yourself …

Posted by:Kate O'Hare