Van Halen has always worshipped at two altars. From their earliest days on the backyard beer-bash circuit, the Pasadena party-rockers toed the line between coolness and credibility. At first, this tightrope act seemed effortless, with David Lee Roth's inimitable swagger playing counterpoint to Eddie Van Halen's mind-bending guitar sorcery.

But after Sammy Hagar replaced Roth in 1985, everything Van Halen did felt laborious. They could still shred circles around their contemporaries, but now they sounded hellbent on proving it instead of letting the songs speak for themselves.

Perhaps nowhere is this shift more apparent than Van Halen Mk II's sophomore effort OU812, released on May 24, 1988. It's a dark, gnarled LP full of labyrinthine guitar symphonies, gut-busting vocals and grooves deep enough to reach the Earth's core. It rocks with abundance, but not with abandon: The band delivers these 10 songs with a stone-faced persistence that matches the somber black-and-white album cover.

When these guys put the pedal to the metal, they're still the best in class. Alex Van Halen's jackhammer drumming powers "Mine All Mine," and Eddie Van Halen's pulsating keyboards and squealing guitars duck and weave around each other. Hagar's at his best while howling like a banshee on "Source of Infection" or rhapsodizing about the rigors of the road on "A.F.U. (Naturally Wired)."

If rock 'n' roll is a sport, Van Halen are Olympians.

Watch Van Halen's 'Finish What Ya Started' Video

Thrash-'n'-burn is just one of many tools in the band's ever-growing kit. The ballads rear their heads again, and they're more stately — and, consequently, less delightfully cheesy — than their 5150 counterparts. "When It's Love" is competent but anonymous AOR fare; "Feels So Good" is a lightweight filler with hotel-lobby keyboards that sound more Genesis than "Jump." The diversification efforts are largely successful: "Finish What Ya Started" coasts on a fat groove, country-rock guitars and Michael Anthony's soaring backing vocals. They're the bassist's most noticeable contribution to the self-produced OU812.

A cover of Little Feat's "A Apolitical Blues," tacked onto the CD version of OU812, best illustrates the album's main pitfall and the chasm between Van Halen's first two eras. Roth led the band through barbershop quartet covers and Motown standards with irreverent braggadocio; Hagar and Co. play their white-boy blues with dogged determination, just like everything else on the LP. Their commitment to the bit is admirable, their virtuosity undeniable — now if they could just sound like they're having a little fun, they could get back to the heart of what makes a classic Van Halen record.

Van Halen Lineup Changes

Three different singers and two different bassists joined the Van Halen brothers over the years.

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