This all-Busnois disc is an early music fan's delight, especially as performed by the four accomplished singers of the Orlando Consort, who convey both the purity of Busnois' music and the many surprises lurking within it. The Mass is the "big" work, almost half-an-hour in length. But interest never flags since the music is unfailingly inventive, the voices perfectly matched, the rhythms buoyant. The Mass is preceded and followed by selections of chansons, a hymn, and a pair of motets. In these too, the 15th-century master of polyphony constantly startles with unexpected twists and turns of the long musical lines. His typically adventurous abrupt changes of rhythm, harmonic twists and turns, and pauses for dramatic effect are all rendered with aplomb. Excellent sound. Top-notch production values include a handsome booklet in readable type with texts and translations, even color reproductions of period paintings. --Dan Davis