Comedy-rock duo Tenacious D, formed 18 years ago by actors Jack Black and Kyle Gass, drop their third album, "Rize of the Fenix," next Tuesday, aiming to save what they see as a dying musical genre.

Six years after their last album, "The Pick of Destiny," they claim to be bringing back "the majesty and the genius" of hard rock while exploring deeper, darker themes on their album. And despite what they see as a bias against their music by some critics because they mix satirical comedy with song, they are completely serious about their newest endeavor.

"Since we had our last album, rock and roll completely died. Thank God for The D, riding in on their white stallions to rescue rock and roll," Black told Reuters in a recent interview.

"What killed it? Was it Axl Rose in the library with a wrench, or was it Lady Gaga in the pantry with the pliers? We don't know but we'll figure it out," he added.

The title track, "Rize of the Fenix" is a rousing country rock-themed ode to the band's attempt to "rise again" that expresses Tenacious D's desire for a chart-topping song, while Black's favorite, "Senorita," is a Mariachi-style tale of a damsel in distress named Conchita.

"We've dug deep for a lot of the jams, such as "Throw Down," our major anti-organized religion song, and "Senorita," a story about a man who falls in love with a woman who can't let go of her abusive relationship. It doesn't sound funny ... we're exploring some deeper, darker material," said Black.

But there is comedy. After all, what would Tenacious D be, without a sense of humor. The songs are divided up by skits such as "Flutes and Trombones," which features Black and Gass getting into a fight over instruments, while "Classical Teacher" sees Gass getting classical guitar lessons.

Still, Black and Gass say they have serious ambitions to crack the mainstream music market, and they have sought advice from Dave Grohl of the Foo Fighters on how to write a hit song.

"I've always wanted to have one of those hits on the radio, but we haven't really been able to crack that code. I think we're trying this time a lot," said Gass.

Black is adamant their third album is "in all seriousness, better than any album out there right now."

"RIZE" TO SUCCESS

Tenacious D was formed in 1994 by Gass and Black in Los Angeles where the duo performed their "mock rock" routines in local bars.

Initially, the success of the band was spurred by Black's skyrocketing fame as a comedic actor in movies such as "High Fidelity," "School of Rock" and Peter Jackson's "King Kong." Gass, also an actor, hasn't seen the same level of success in Hollywood, but the duo insist their chemistry remains unaffected by Black's Hollywood A-list status.

"I go and do some other stuff, but I always come back to the D, because it's the best stuff, it's the stuff I get the most satisfaction for ... On Tenacious D island, all things are equal, me and Kyle are on level-playing fields," said Black.

In 1997, Black and Gass performed in an HBO TV show based on their journey as a band, producing three half-hour episodes and two short sketches each that aired through 2000.

As their fame grew, the joke morphed into a serious endeavor, and in 2001, the duo released their debut self-titled album. It featured a backing band comprised of Grohl on drums, The Vandals' guitarist Warren Fitzgerald, Redd Kross bassist Steven Shane McDonald and Phish keyboardist Page McConnell, and it eventually went platinum, led by the song "Tribute."

The second album, "The Pick of Destiny," was combined with a Tenacious D film of the same name and a world tour, but failed to achieve the same level of success of the first album, although the film became a cult hit through DVD sales. To date, the band has sold more than 3 million albums worldwide.

Still, there is a sense of frustration for Black in Tenacious D not being taken seriously as a credible rock band. He feels critics overlook their talents due to the satirical content, but he has faith the band's loyal fans see them differently.

"I do love (Jack White's) "Blunderbuss," I love the Foo, I love Tom Waits, his new record is incredible ... and Goyte ... but our album is better than all of those, and because we're clowns, we don't get that kind of love," he said.

"In a hundred years' time, no one will remember Gotye or the rest, but the shining beacon of The D -- they're going to start religions after us."

(Reporting By Piya Sinha-Roy; Editing by Bob Tourtellotte)

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