"THE PACIFIC AGE." Orchestral Manoeuvres in the Dark. A&M. There was a time when this band sounded almost minimalist, but that was six years and seven albums ago, before they hit with more lavish material, before "If You Leave" from "Pretty in Pink" and long before "The Pacific Age," in which there's nothing minimalist about their sound or their commercial ambitions. OMD bloats its ballads with unnecessary pomp: "The Dead Girls" drags in operatic background vocals and symphonic flourishes, while "Southern" sets Martin Luther King to music, adds narration about the problems of black Americans and is about as convincing as C. Thomas Howell in "Soul Man." At its best, OMD whips up imaginative, attractively textured pop music that sounds fresh but familiar. The band would be more likeable if it found a middle ground between what it used to be and what it's become.