For a music critic, unconditional praise for a recording can be a dangerous thing--but what else can you do when you hear something that's unquestionably among the best in its class? This interesting release, which contains performances made in 1997 and 1998 in Denmark by the chamber ensemble known officially as Vocal group ARS NOVA, features nothing less than first rate singing and repertoire to match--although most listeners will be unfamiliar with the works at hand, late-15th-century church music that can stand equally with many better-known pieces by Josquin, Dufay, or Ockeghem. The writing exhibits fluid melodies and vibrant harmonies that make the most of vocal ranges and timbre within a rich, colorful, highly refined polyphonic fabric--all the things that the best composers of the period understood and exploited. A perfect example of Obrecht's mastery of idiomatic vocal writing is the three-part Ave maris stella, for soprano and alto voices. If there's such a thing as a masterpiece that lasts only two minutes and 10 seconds, this work--which sounds like angel-song reverberating in the heavens--certainly qualifies.

Of course, the whole thing depends on the singers, and the dozen or so members of this world-class ensemble (founded in 1979) are as well-matched and technically accomplished as any of the best practitioners of this repertoire--the Tallis Scholars come immediately to mind. Paul Hillier, who became principal conductor of this group in 2002, has a distinguished reputation for musicologically sound interpretations of early music--but he never neglects to ensure a memorable sonic impact on the listener, through sheer beauty of the voices and the power of perfectly balanced and blended ensemble. Here, he does it again. If you love choral music, don't miss it.