Gwen Stefani, Pharrell Williams debut as judges on 'The Voice'

Stefani joined singers Adam Levine, Blake Shelton, and Pharrell Williams on the judging panel for the reality singing competition. 'He really has no filter,' Stefani said of her fellow judge Levine.

Gwen Stefani is surrounded by men. She has three sons with husband Gavin Rossdale and is the only female in her rock band No Doubt.

But the 44-year-old singer and fashion designer said joining the all-male coaching team on NBC's reality singing competition "The Voice" has tested her tolerance.

"I have to say Adam (Levine) has really, you know, the bar has been risen with him. He really has no filter. And it's just really shocking," Stefani joked in a recent interview.

The Maroon 5 frontman isn't apologetic.

"I don't care about saying things because people find a way to get mad at you about anything you say," he said. "So I'd rather it be like gross and funny and outlandish than like boring."

The seventh season of "The Voice" premiered on Sept. 22 with Levine, country star Blake Shelton, and newcomers Stefani and Pharrell Williams.

Levine, who recently married Victoria's Secret model Behati Prinsloo, warned it could be his most outrageous season yet.

"I'll probably lose more of my filter now that I'm married because I could never shock or offend my wife's sensibilities because she's too like me," he said.

Williams said working with contestants has been a "magical" experience and one that he takes very seriously.

"We have a different level of talent. Like nothing laughable, you know? ... Like it's serious. It's serious competition," the "Happy" singer said.

Shelton said Williams has already nabbed many of his top contestants.

"Pharrell is a guy that makes you think that he's this really friendly, you know, a very thoughtful person," said Shelton. "He's conniving, he's sneaky, and he's very good-looking and he uses that against us."

Rossdale and Fleetwood Mac's Stevie Nicks will lend a hand as advisers to the singing hopefuls.