One Halloween, when singer Robin Gibbens was 6 or 7, he couldn't decide whether he wanted to be disco icon Andy Gibb or KISS guitarist Ace Frehley.

In a move that would later prove prophetic, Gibbens opted to be both.

"I ended up making my dad buy me an Andy Gibb and an Ace Frehley costume," Gibbens said. "I went out that year with Ace Frehley's outfit and an Andy Gibb mask ... Ace Gibb."

These days, Gibbens is still mixing hard rock and disco, albeit in a more kitschy way. Gibbens is the lead singer of Tragedy, the world's premier all-metal Bee Gees tribute band. Now 36, he has traded the Halloween costume for tight, white '70s pants and a chest-baring button-down shirt.

Gibbens and his bandmates wail through the Bee Gees' trademark harmonies like wild banshees, and crank the distortion on their guitars to the max. They're blending metal and disco - two of music's most ridiculed genres - with a flashy, tongue-in-cheek attitude that few bands can match. Friday, they'll come to Rams Head Live.

"I just think, 'Wow, I'm awesome,' " Gibbens deadpans. "There's not a day that goes by that I don't marvel that I can do this and get paid for it. ... It's been totally mind-blowing for a band that wasn't meant to go anywhere to get this far."

To no one's surprise, Tragedy started out as a joke. The group got together to play a couple of gigs for friends in New York City one weekend in August 2007. It wasn't meant to go any further than that. They made a MySpace page and recorded a hasty demo of "Staying Alive" to help promote the shows. Then destiny called.

"We never thought we'd record an album," said Gibbens, whose real name is Jake Szufnarowski.

"All the sudden, offers started coming in. People started asking us to play more and more. We were like, 'All right, we'll play a show here, we'll play a show there.' "

Last year, Tragedy, which is based in New York, toured Britain three times and performed at a festival in front of thousands. Tragedy's set includes all the Bee Gees favorites, as well as some songs the Gibb brothers wrote for others, such as "Grease" and "Islands in the Stream." The Bee Gees' music lends itself perfectly to metal reinterpretations, Gibbens said.

"It's the best material to work with," Gibbens said. "The melodies were phenomenal. They just needed some crunch. They needed some distortion pedal."

Tragedy's version of the Bee Gees' anthem "Stayin' Alive" kicks off with a heavy drumbeat and distorted guitars blasting the song's familiar riff. Then a piercing Axl Rose-like wail - grating enough to peel the paint off a wall - seems to come out of nowhere.

Only then is it time for the first verse, delivered with a thick metal attitude: "Well you can tell by the way I use my walk / I'm a woman's man / No time to talk."

Though Tragedy sells a fair number of albums, Gibbens said, they can't compare with the Bee Gees. But that's not necessarily Tragedy's fault, he said.

"It doesn't mean we're less popular than them, it's just a sign of the times," he said. "Record sales have been down lately. It's an industrywide phenomenon. It's not just us."

Either way, Tragedy does better than Gibbens originally thought it would. It's been so long since either disco or metal were all the rage, people can step back and enjoy the cheesiness for what it is, he said. And the quality of the Bee Gees' catalog speaks for itself.

"We're ageless, dude," Gibbens said. "A great song's a great song. You can do it any way you want."