Let's just say this bluntly: "Omnis", by the enchanting Irish a cappella choral group Anuna, is one of [the] top Celtic CDs of 1997. The 14-member classics group is devoted to the cultural heritage of Ireland's turbulent past. Not that it's work is bound by the Emerald Isle: Early Christian and Medieval hymns. English plainsong and the songs of the German mystic, artist and abbess Hildegard of Bingen are among it's many influences. Sung in Irish, Latin, English and Scots-Gaelic - sometimes several in the same song - Anuna delves into authentic ancient texts, often with a vibrant contemporary flair.