Megadeth On The Mend -- Lead Singer Mustaine Puts His Dark Days Behind Him

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Megadeth and Corrosion of Conformity, 7:30 p.m. tomorrow, Arena; $19.50, 628-0888. -----------------------------------------------------------------

For those of you who saw Megadeth the last time the hard-rock/metal band played here, in late 1992, Dave Mustaine would like to apologize.

"We had a really peculiar performance last time we were in Seattle," the band's lead singer-guitarist said in a phone interview from Philadelphia. "That was a really unstable time in my life. Hopefully the people that went will give us the benefit of the doubt and come and see us this time, because the band is much more stable and things have changed immensely."

In February 1993, shortly after that Seattle show - which was well received by the audience despite the fact that Mustaine was in bad form and cut the set short - he entered a rehabilitation institute, following a near-fatal overdose of Valium.

He was also, he has said, addicted to heroin and was abusing other drugs.

Mustaine's confessions shocked many fans because he has always been one of the most intelligent, articulate figures in metal. His songs, despite their fascination with the dark side, emphasize individuality and freedom, and caution against dependence on drugs or anything else.

The band came to a standstill while Mustaine went through rehab. It's just now reconstructing its career. "We're doing a preliminary run through the States to reestablish ourselves in the marketplace," Mustaine explained, "because I think a lot of people thought we were dead."

The release of the band's latest album, "Youthanasia," on Halloween, and the current "Youth in North America" tour, which started last month, on Friday the 13th, are altering that perception.

"It was very questionable whether or not we were going to be able to continue to live up to the standards and expectations (of the fans)," Mustaine said, "and we've been pretty much unraveling that belief, dispelling that myth."

"Youthanasia" debuted at No. 4 on the Billboard chart, and has already gone platinum. The tour is going so well, Mustaine said, that the band is planning major stadium dates in the summer.

It has also enjoyed a couple of recent well-publicized appearances on David Letterman's show. Letterman had fun with the band. He became "MegaDave" and guest Drew Barrymore "MegaDrew." The even had their own logos, a la Megadeth's.

"He never does that with any other band," Mustaine said. "He really digs us."

Mustaine said Letterman displays the kind of acceptance the band strives for. "I truly believe that when you can see the spirit of the band you can see the beauty that lies within us. A lot of times people don't really capture our spirit."

For instance, he said, detractors, and even some fans, don't realize there's a heavy dose of black humor in the songs.

"It's definitely tongue-in-cheek," he explained. "I mean, if you don't have a sense of humor, if you take yourself too seriously . . . you end up like Sting, trying to save the rain forest, trying to save the oceans, trying to save the walruses. How about trying to save your hair, buddy?"

As "Youthanasia" attests, Megadeth is more melodic that most metal bands. Mustaine doesn't scream his vocals, he actually sings them. And he and Dave Ellefson, the band's other guitarist, play clean, crunchy riffs loaded with variety and inventiveness. At a time when other hard rock bands are fading, Megadeth is thriving.

Mustaine chose Corrosion of Conformity as the tour's opening act "because I felt that they were young and they they deserved to be treated well and to get a break."

The North Carolina punk/metal quartet is enjoying radio airplay with the Hendrix-inspired "Albatross," off its new "Deliverance" album.