The New York Times March 18, 1990, Sunday, Late Edition - Final LOVE AS A BURDEN, A CALLING AND, SOMETIMES, A CATHARSIS By JON PARELES Centuries ago, an Irish poet, a woman whose name has been lost, wrote: My love is no short year's sentence. It is a grief lodged under the skin Strength pushed beyond its bounds; The four quarters of the world, The highest point of heaven. It is A heart breaking or Battle with a ghost, Striving under water, Outrunning the sky or Courting an echo. Sinead O'Connor may never have read that poem (which appears in John Montague's 1983 anthology, ''The Book of Irish Verse''), but she becomes one of the poet's heirs with her second album, ''I Do Not Want What I Haven't Got'' (Chrysalis 21759; all three formats). The songs, which are inseparable from her singing, are dry-eyed and grief-haunted, tender and baleful, stoic yet flecked with fury and despair. Their settings can be as blankly modern as a computer display, while the melodies evoke age-old Irish traditional music. And the tone of Ms. O'Connor's voice is clear and assured, almost impassive in its purity, until it suddenly breaks into a keening cry. Ms. O'Connor, now 23 years old, was still in her teens when she emerged from Dublin's folk and rock circuit - first as a singer on the soundtrack for the the 1986 film ''The Captive,'' composed by U2's guitarist, the Edge, and then with her 1987 debut album, ''The Lion and the Cobra.'' Her shaven head and piercing gaze made her stand out; so did songs that could be opaque and enigmatic or brutally direct. Like most debut albums, ''The Lion and the Cobra'' paraded its diversity, as Ms. O'Connor's own production moved from traditionalist ballads (swathed in guitar noise) to rock to dance music to orchestrated mini-epics. Her voice made one song a lullaby, the next a snarl or an almost playful tease; the music was windblown and unpredictable. While Ms. O'Connor had soaked up the music of 1970's singer-songwriters like Joni Mitchell, she didn't accept any old-fashioned, gentle-crooner image; she had a 1980's edge. Her bald pate (now grown out to a crew cut) and thick-soled shoes came from the wardrobe of post-punk hard-core rock, and her singles remade songs from the album into collaborations with a rapper, M. C. Lyte, and with the shrieking, bluntly sexual performance artist Karen Finley. With ''I Do Not Want What I Haven't Got,'' Ms. O'Connor has become more somber and more intransigent. She uses virtually the same collection of styles she unveiled three years ago, but now with a deeper melancholy. As on her first album, the songs revolve around betrayal, obsessive longing and, in the title song - an unaccompanied parable about a pilgrimage - the possibility of transcendence. But where ''The Lion and the Cobra'' often drifted into inscrutability, this time Ms. O'Connor usually makes herself plain. Like the anonymous female bard, Ms. O'Connor sings of love as a burden, a calling and a catharsis - a purifying martyrdom. The 10 songs on the album have little to do with pleasure and nothing to do with romance. ''Jump in the River,'' the closest thing to a good time, is a chugging, Pretenders-style three-chord rocker that Ms. O'Connor sings with a throaty seductiveness. It describes an all-consuming infatuation, ''a gorgeous mistake'' grown into a desire so strong that, ''If you said jump in a river/ I would because/ it would probably be a good idea.'' In most of the other songs, love is already gone, transmuted to pain and responsibility. The album recounts breakup after breakup, recalling them in a voice that moves from dignity to rage. In ''Feel So Different,'' Ms. O'Connor is backed by a stately, Baroque-style string orchestra while she sings, steely-eyed, ''I should have hatred for you/ But I do not have any.'' ''The Last Day of Our Acquaintance'' begins with slowly strummed guitar as Ms. O'Connor quietly notes, ''I'll meet you later in somebody's office,'' and adds a band while she retells the situation until she sobs, or shouts, ''You won't listen to me!'' ''The Emperor's New Clothes,'' about outgrowing a mentor who may also be a lover, seems autobiographical: ''How could I know what I want when I was only 21?'' ''Nothing Compares 2 U,'' written by Prince (and first recorded by a band called the Family), becomes an eerie dirge. Over sustained string-orchestra chords and logy drums, as barren as cinderblock walls, Ms. O'Connor's voice grows thin and breaks as she sings the operatic upward leap of ''nothing compares,'' then turns nasal, clenched and dissonant as she rushes to add, ''to you.'' As it does throughout the album, the uninflected backup only makes her voice sound more desperately human. For Ms. O'Connor, love is never far from death. ''I Am Stretched Out on Your Grave'' (based on a poem about a young man mourning his dead love by Frank O'Connor, who is no relation) sets a modal, Celtic-sounding melody above an unswerving drumbeat fit for a rap record. Ms. O'Connor uses the tense tone and quavering ornamentation of a traditional Irish ballad singer, answered from above by her own wordless, ghostly ''ah's'' and finally by a Celtic fiddle. ''Black Boys on Mopeds'' wrenches Ms. O'Connor into daily life: she denounces an England where policemen shoot ''black boys on mopeds'' and decides to leave in order to save her own children from such racism and violence. And ''3 Babies' ' merges love, mourning and maternal protectiveness in an ambiguous lullaby. Through most of the album, the lyrics by themselves present a pre-feminist persona - the singer defined by the absence of her man and by her children. ''I really am soft/ yes/ tender and sweet,'' she sings in ''You Cause as Much Sorrow.'' But the music transforms the message. In nearly every song, there are moments when Ms. O'Connor's voice tears the music apart, like a Bacchante rending her garments. Yet she hasn't lost control; she can repeat ululations or snarls exactly where she wants them, and her arrangements crest with triumphant choruses. Her voice tells listeners that she knows about pain, vulnerability, obsession, but her calm authority - the composure of someone who has survived to recount her sufferings - insists that she will endure.