Like the Clash, X broke out of a rock scene imploding on manic energy and rigid stylizations to become one of rock's most critically acclaimed bands--and one that mattered.

It's not that X snubbed or transcended the scene that spawned it--in its case, Los Angeles' hard-core battleground, circa 1978-79. It's just that, from the start, two first-rate bohemians such as John Doe and Exene, X's husband-and-wife singing and songwriting team, were determined to march to beats pulsing deeper in America's worn psyche than the simple clamor of punk would allow.

However, unlike the Clash, which has embraced a vitiating brand of political and musical internationalism, X (who will appear at the Ontario tomorrow night) has stuck close to home. Its third album and first for a major label, "Under the Big Black Sun" (Elektra 60150), reaches even deeper into rock's musical vocabulary and the personal lives of the band members than did last year's sensational "Wild Gift." The result is the same--another harrowing and, in its own fashion, exhilarating showdown with those late-night realities that have always cast an eerie glow on the American mythology of love, marriage and success. Of course, it's the contemporary America of rapidly shrinking opportunities that lies "under the big black sun"; and, in the title cut, Exene sums up her options with the spare, existential detail of Samuel Beckett: "If it isn't men, it's death."

"Under the Big Black Sun," one of the album's best cuts, is a storming rocker led by Billy Zoom's ringing guitar theme and D.J. Bonebrake's booming drums. Exene sings this elliptical tale of her sister's death, summoning a harpy's fury on one verse, trailing off to an eerie wail on another and ending with a fatalistic couplet that is as poetic as it is dreadful: So one has a smoke one has a drink the man is gone, Mary's dead good morning midnight.

While some have traced the band's doomy beat vision to the Doors' Jim Morrison (after all, the band's producer is ex-Door Ray Manzarek), the brilliant lyrical and musical expanse of the album placed the band in a longer and nobler tradition of American musical poets.

For example, listening to a teary-eyed Exene cry out for her lover in "Come Back to Me," a lilting blues that dreamily fades on a smoky sax riff, recalls the world-weary romanticism of Billie Holiday. In fact, X's depressive realism, animated with striking images snatched out of life's routines, are of a piece with the mournful cry of the Appalachian ballad and Hank Williams and with the piercing nihilism of mid-period Dylan and Lou Reed. The band even reaches back for a fancifully swinging treatment of Leadbelly's "Dancing With Tears in My Eyes," a song, like many of the band's originals, about having the wrong person in your arms.

While casting X within extended musical and lyrical traditions in this way may sound incongruous or even compromising for a band nurtured at punk's bosom, it's really not. X's ability to convincingly illuminate the dark side of Americana is built on the sheer uncompromising power and verve of its rock 'n' roll. On "The Hungry Wolf" and "Riding With Mary," X achieves an intense, apocalyptic sound that surges and subsides with unpredictable rhythmic undertows, while John Doe's and Exene's unearthly, discordant harmonies float precariously above. The instrumental hero throughout is drummer D.J. Bonebrake, who can pummel the songs into a corner with the force of a sledge hammer and swing them right out onto the dance floor again with the assurance of a jazz man.

One of the reasons X matters so much is because the unrelenting stares John Doe and Exene mercilessly cast at the world are so honestly reflected back on themselves. "Because I Do" is a furious start-and-stop rocker that is ironically undercut by Exene's resigned enumeration of the marriage condition: "I'm not a fool just a bride and I'm just no good inside I am the married kind the kind that said I do forever searching for someone new.

There is a constant dialogue on temptation and adultery that runs between this husband-and-wife team, one that accepts both the weakness of the flesh and the anguish of infidelity with a shrug. And in "How I Learned My Lesson," Exene, ever the poetess, takes only two brilliant lines to summarize the contradictory messages of the human heart and the push and pull of her own marriage: I'm wrecking the kitchen carefully but I'm keeping your dinner warm.