By Annie Barrett
Updated September 15, 2011 at 12:00 PM EDT
Trae Patton/NBC

America’s Got Talent crowned jazz singer Landau Eugene Murphy Jr. its season 6 winner on Wednesday’s star-studded finale, prompting many fans to wonder why — aside from season 2’s Terry Fator, who also sang sometimes in his acts — the winner of AGT has consistently been a solo singer.

“I think it just depends on the voters’ criteria,” executive producer Jason Raff tells EW. “Is their criteria ‘a Vegas act’ or just ‘someone they think is amazing and the best act in America’? Some people just want to pick someone who they think is really talented. It may be easier for them to identify sometimes with a single person as opposed to a group. When you know a single person as ‘Landau’ as opposed to [fellow finalists] iLuminate or Silhouettes, which is just a bunch of people — you know, people might love it and think it’s an amazing act, but they just don’t get motivated to pick up the phone.”

Does the influence of shows specifically about singing — NBC’s The Voice, Fox’s American Idol — condition viewers to feel like they should be voting for singers? “Maybe,” says Raff. “I will say I do think that if there’s any advantage at all to singers, it’s that they can come out and just sing another song each week. If you’re a variety or a dance act, coming up with a brand new routine that’s something new and different is more of a challenge. It it a lot of work to choreograph 10 people as opposed to just sing another song. I don’t know if everyone keeps that in mind when they pick their favorites.”

Would AGT ever consider doing a season with no solo singers? “I think that’s a possibility,” said Raff. “But the thing that brings me back to the show every year, from season 1, is it’s open to any age, any talent. We are the only show. The X Factor has a more broad [age] range of singers, but still has age restrictions on the low end. We had our youngest contestants with Ellie [White] and with Silhouettes. I just love that it’s open to everyone. I always hope that the acts win, but to be honest, to me, it really doesn’t matter who wins.”

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