Def Leppard guitarist Phil Collen has been keeping himself incredibly busy lately, and fans will soon reap the benefits -- the debut from Collen's "extreme blues" side project, Delta Deep, is on the way, along with a new full-length album from Def Leppard.

Collen discussed the Delta Deep sound during a recent appearance on Chris Jericho's 'Talk Is Jericho' podcast, explaining, "It's extreme blues, or we're calling it alternative roots, 'cause it's really over the top. It started off being bluesy, but when we started recording electric, it ended up sounding more like Led Zeppelin."

Delta Deep's Facebook page describes the band as sounding like what might happen "If Aretha Franklin & Chaka Khan were in Led Zeppelin's band," an intriguing blend that Collen attributes to the unique talents of his wife's godmother, singer Debbi Blackwell-Cook. "She's this black woman, 60 years old, who sings her ass off. It's kind of like a cross between Chaka Khan and Tina Turner; it's that kind of really powerful voice. And Robert DeLeo, who plays bass with Stone Temple Pilots, he's playing bass. He's on it and he's killing it. We're actually recording with him at the moment, and it's amazing. And [drummer] Forrest Robinson ... he's the ultimate rock drummer. So just the four of us have managed to get this monstrous sound."

He went on to promise a "way more aggressive" approach to his instrument with the new band, saying, "I mean, it's still obviously me playing guitar, but it's a very different approach. Not knocking a lot of the blues stuff that's around these days, but it's very tired and the same old thing. What we're doing with this, it's very aggressive...I've never heard blues like this. It almost sounds like Rage Against the Machine does Muddy Waters, if you can imagine that."

Meanwhile, work continues on the new Def Leppard album, which will be the band's first since 2008's 'Songs from the Sparkle Lounge.' He'd earlier intimated that the band might settle for an EP, but a recent songwriting session left the group with more than a dozen songs in various stages of completion -- and it's apparently all because of a vegan diet.

"We got about 15 songs started. What we thought was going to be an EP has now definitely turned into an album of new Def Leppard material," Collen told Classic Rock Magazine. "The whole time we were there, the incredible gourmet chef Jeni Cook put the band on a raw vegan food diet – no, it's not just lettuce. We were treated to some of the tastiest foods I've ever had in my entire life. We had raw vegan desserts every day, along with sushi, pizza, Mexican-style wraps and incredible salads. The coolest side effect was that I lost seven pounds, while keeping all of my energy and strength up."

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