Garbarek and the Hilliard Ensemble waited nearly five years before trying to follow up their surprisingly successful Officium album, but finally they came through with an even more adventurous two-CD set of jazzman-meets-early-music-voices. Here, their range straddles no less than three milleniums (just missing a fourth by a couple of years), from the "Delphic Paean" of Athenaeus circa 127 B.C. to a lullaby by the contemporary Estonian composer Veljo Tormis, with intervening contributions by Hildegard von Bingen, William Billings, and Thomas Tallis, Iroquois Indians, Basque and Peruvian folksongs, and many more far-flung choices. Most daringly, the four voices themselves now start to improvise on scraps of ancient material culled from old book bindings and the like, though it's hard to determine exactly where this occurs (probably during some passages of wordless vocalise). Ultimately, despite the freer methods, the results are often pretty much the same as Officium on disc one -- soothing, timeless sonic frescos reverberantly recorded in the same Austrian St. Gerold monastery, with Garbarek soaring over or threading through the texture ever more sparingly. Yet on disc two, Garbarek and the Hilliards start to move into other worlds, breaking into something more disturbing and even atonal in that ancient "Delphic Paean," the syncopated harmonies of Garbarek's own "Loiterando," or a strange-sounding Russian Psalm from the 16th century. This is a collaboration in transition, and one hopes it will continue to evolve.