The Washington Post May 7, 1990, Monday, Final Edition Sinead O'Connor Mark Jenkins Giving a new meaning to the phrase "black Irish," Sinead O'Connor's current album, "I Do Not Want What I Haven't Got," marries slow-burn soul to the Celtic folk-rock more commonly associated with contemporary Irish bands (including her own former outfit, In Tua Nua). It's an intriguing synthesis, but one that would be more intriguing if the results weren't also sort of boring. Aside from "Nothing Compares 2 U," the Prince song she rode to No. 1, the album is largely unblemished by tunefulness and provides few songs that seem likely arena-rousers. Such skepticism was defied -- at least partially -- by the Sinead O'Connor who appeared Saturday night at GWU's Smith Center. The singer and her songs, some rearranged for more punch, proved utterly arena-ready. Indeed, her show -- carefully choreographed, broadly melodramatic, even color-coded (red for O'Connor, black for the band) -- could only be called slick. That was fine with the sellout audience, which greeted each trill or growl of O'Connor's versatile voice with rapturous tumult and roared when she removed her nunlike red cowl to reveal her trademark close-cropped head. The crowd even stayed with her during a long and somewhat tedious solo set in which she was accompanied only by acoustic guitar or (for the hip-hop lament "I Am Stretched on Your Grave") a tape recorder that had been wheeled out on stage. After her extensive tour of downbeat "Do Not Want" material, O'Connor wisely turned to "Jerusalem" and "Mandinka," two livelier songs from her first album, to close the show. Along with the few other songs she performed from that album, these were the highlights. The five-piece band, driven by drummer (and husband) John Reynolds's spare but canny beats, grounded O'Connor's histrionic tendencies in distinctive hard rock. Though the characteristically extreme final words of her final song -- "You're a [expletive] liar" -- also were greeted with cheers, they rang false. O'Connor can't credibly be both Angry Young Woman and crowd-pleasing mainstream pop star, and she has clearly chosen the latter. She returns to Washington Aug. 26 to perform at Merriweather Post Pavilion.