As you might know, guitarist Dave Mustaine, with bassist David Ellefson, formed Megadeth in 1983 after a short and stormy stint in Metallica. It was no surprise, then, that Ulrich's comments packed a punch with Megadeth; what's more, Ulrich's words were particularly timely: Megadeth was just starting work on its new CD, the appropriately titled Risk.

"I think obviously a comment like that coming from somebody like Lars Ulrich has a lot of validity," Ellefson says. "They're a band that obviously took a lot of chances, and it paid off for themŠ.But I think at this time and place, where Megadeth is at, and where our type of music fits into the world, I just think the time was now [to take a risk]. Let's just go for it and really just roll the dice and see what happens."

It's hard to gauge, however, how much of Megadeth's rejuvenation is due to Ulrich and how much is due to the band's own desire to press against the known boundaries. When talking with Ellefson, one gets the sense that Megadeth, which includes guitarist Marty Friedman and new drummer Jimmy DeGrasso, would have pushed its music in new directions even without prodding from a respected musician.

In fact, Cryptic Writings had signaled the beginning of a new chapter for the venerable heavy metal band. While Megadeth's early albums, Killing Is My BusinessŠ And Business Is Good! (1985) and Peace SellsŠ But Who's Buying? (1986), were speed metal before it had a name, subsequent albums such as Rust In Peace (1990) and Countdown to Extinction (1992) were varied in approach.

Cryptic Writings, the band's eighth CD, introduced a greater amount of melody to Megadeth's music than ever before. It was also the first Megadeth CD to be enthusiastically embraced by radio. "Trust," a rocker accented by a brief acoustic interlude, became a chart-topping hit on rock radio, while three other songs from Cryptic Writings went Top 10 on national playlists.

But as the band members finished touring behind that CD and pondered their next move, they realized they wanted to diversify the Megadeth sound even further on the next CD. Consider it mission accomplished. In fact, Ellefson believes Risk is the band's most adventurous work since Countdown to Extinction, the album generally considered the band's biggest stylistic step forward to date.

All of this boundary pushing was motivated by some experiences on the road in the early 1990s. "We had just finished a tour called 'Clash of the Titans,' " Ellefson says, "and we were on that tour with some other contemporaries of ours at that time, Anthrax, Slayer and a new band called Alice In Chains that had a very new sound, very fresh. And even though our audience wasn't responding that favorably to [Alice In Chains] at that time, we noticed that they had something new and fresh to offer."

It was at this point, Ellefson says, that Megadeth realized the speed and thrash metal scene was dying. If the band was going to continue, it was going to have to reshape its sound. Call it survival instinct. The band took that attitude into the studio at the time it recorded Countdown to Extinction, and it has kept it burning on all subsequent works.

"That whole heavy metal scene, it's almost become obsolete, and it's almost disappeared because some of those fans have grown up," says Ellefson of the time Cryptic Writings was released. "They don't go to concerts anymore. They don't buy records anymore. [But] there's a whole other side of music and a whole other type of fan out there buying records and going to concerts."

The more melodic direction that emerged on Cryptic Writings is even more pronounced on Risk, particularly on "Breadline" and "I'll Be There," two mid-tempo songs that mix pop and metal sensibilities. But that's just the start of the stylistic variations. The lead track and new single, "Insomnia," represents the biggest departure. With its programmed rhythms, Middle Eastern motif and industrial edge to its crunching guitars, the song represents a dramatic, and successful, shift in texture and tone for Megadeth. Two other songs, "Wanderlust" and "Ecstasy," stick to more traditional guitar-bass-drum instrumentation but offer sinister and sensual moods that are also slightly different from typical Megadeth concoctions.

It's also worth noting that a long-standing Megadeth trademark, the double-time bass drum work and staccato guitar riffing that defined speed metal, is virtually absent from Risk. Hard-rocking songs like "Prince of Darkness," "Time: The Beginning" and "Time: The End," three songs most likely to satisfy longtime fans, seem more rooted in '70s metal than in the shredding tones popularized by such bands as Megadeth, Metallica and Pantera.

Ellefson credits Dann Huff, who also produced Cryptic Writings, for assisting Megadeth in finding new musical directions to pursue. "Dann really helped us because we were able to take a lot of Megadeth ideas, and by putting a new groove or a new rhythm underneath us, all of a sudden we've got a Megadeth song that sounds new and fresh and exciting," Ellefson says. "Certainly 'Ecstasy' was a perfect example of that."

Another key contributor to the shift in Megadeth's music has been Bud Prager, who, along with Mike Renault, took over management of the group after the 1994 CD, Youthanasia. Prager, in fact, shares writing credits on five of the 12 tracks on Risk.

Ellefson says Prager helped clarify roles within the band, keeping Mustaine as primary songwriter, while encouraging Friedman, whose tastes include the Beach Boys, Elvis Presley and the Carpenters, to contribute more to songwriting. Prager also pushed Ellefson and DeGrasso to find ways to kick-start the rhythm section of the band.

"Bud was very instrumental in helping shape the direction and mentality of us to go in and make Cryptic Writings," Ellefson says. "He is very much responsible for helping reinvent Megadeth as just a viable bandŠ.He was able to come and see Megadeth for what we are, see it for where it was headed and be able to turn the ship a little bit and make sure that it goes in a new direction so that it doesn't just go over a waterfall and crash."

Megadeth performs Tuesday, December 21, at the Aerial Theater, 520 Texas. For more information, call (713)629-3700.