Gwen Stefani's This Is What The Truth Feels Like Tour with Eve is now in full swing, which means the No Doubt pop icon is on her promo grind.

During an appearance on The Howard Stern Show yesterday (July 20), the "Misery" singer gave us plenty of truth — blunt, honest truth — about her vocal skills while discussing her collaboration with Prince over fifteen years ago.

Back in 2001, Gwen came to Minneapolis to work with The Purple One, then called The Artist Formerly Known as Prince, on a song called "Waiting Room" from No Doubt's Rock Steady. Admittedly, she says, it was "super scary and intimidating."

"I went in the booth and I did not come out for, like, eight hours...I was so scared because I'm not even that good of a singer," she revealed. And while Stern protested Gwen's statement ("I think your songs are hard to sing!"), she went in even further on herself.

"I'm saying technically, as a singer, I kind of have my style or whatever, but it's not like I have a big range. Do you know what I mean? I can sing in tune, and I can hear notes, but he's just like a genius."

Did you hear that, Shirley Bassey? She doesn't have the range.

Prince loved it, however, and told Gwen that the session reminded him of working with Wendy & Lisa.

"I'm just sitting there going 'Is this happening to me right now?'" Gwen said.

The song ended up making the cut — listen to "Waiting Room" now — and that wasn't the only interesting insight Prince had for Gwen.

The two first met years before while No Doubt was in town for a concert, where Prince came to see them play.

"He did tell me some interesting things, though. It was right around the time when Jennifer Lopez was putting out her stuff. 'Waiting For Tonight,' remember that song? I remember him, we all went out one night in a white limousine. He took us out, and he said 'that's your competition'," Gwen revealed.

"I was like 'What do you mean? That's nothing to do with me? That's Jennifer Lopez!'," she laughed. "I've never told Jennifer that, hopefully she'll hear. It was interesting. He just was up on everything."

Jenny and Gwenny: musical rivals? They exist within the same general pop sphere, for sure...but I can't say I really see that comparison, either. Still, fascinating.

Listen to Gwen's full Prince story up top.

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