Extreme guitarist Nuno Bettencourt has been in an unlikely situation lately -- touring with pop superstar Rihanna -- and he's found himself impressed.

"Whatever people's perceptions are of whatever Rihanna is, it's definitely a different animal live — completely different," Bettencourt tells Guitar Interactive, in the above video. "At first, even when I went to work with her, I was, like, 'Can she really sing?' A lot of times with the singers you hear now, there's a lot of that Auto-Tune element and you don't know who can really sing. But when I went to rehearsal, I could not believe how well she sang, and I could not believe how well she sings live."

There's also been a lot more room for guitar than Bettencourt's initially guessed -- and that's what got him interested in the first place. He'd actually "been asked through the years to do stuff ... not just necessarily pop artists but with other rock bands, and I've always declined." Then, not long after finishing the latest Extreme tour, a musical director friend of Bettencourt's approached him about a Rihanna gig -- and, this time, included an enticing promise.

"I was, like, you know what? I'm in my 40s, I've been sticking to my guns for so long and not doing anything else," Bettencourt admitted. "'Cause at first I said, 'No. Why would I wanna do it? There's really no guitar in that stuff.' And he said, 'Well, that's the thing. She wants it to be a lot heavier live.' And I'm, like, 'So I get to do what I do.' And he goes, 'Completely. Your rig ... ' [And I said], 'I get to ruin every one of her songs?' And he was, like, 'Yeah.' So I thought that would be fun."

And, Bettencourt says, it has been. "The hats that you have to wear, feel-wise -- you go from a basic pop song like 'Umbrella' to to reggae song to a club track to even, like, a punk song and R&B stuff," Bettencourt says. "So the amount of different textures and feels, and to have to play along with these incredible musicians who hear everything, it's definitely not a punch-in-the-clock-type situation for me. Live, it keeps you busy. ... It sounds crazy, but it's really challenging. It really is."

Bettencourt released his first solo album, 'Schizophonic,' in 1997. He's also been part of Perry Farrell's Satellite Party. His Extreme collaborator Gary Cherone has worked with Van Halen and, more recently, with Hurtsmile. The latter recently released ‘Rock N’ Roll Cliche,’ a song that dates back to Cherone's aborted follow up to ‘Van Halen III,’ his lone release with Eddie Van Halen's band.

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