This is the sort of recording that requires an article rather than a two- or three-paragraph review. No part of this program--including the 14th-century Machaut Mass--is what you'd call "easy listening"; indeed, it may take a third pass through the title work before the ear discerns a larger, apprehensible musical entity growing from its multilayered, multirhythmic structure. Happily, Orlando Consort tenor Angus Smith's notes give us helpful descriptive details regarding Tarik O'Regan's work, which attempts to combine two 14th-century texts, each of which "toys with the ambiguities of intertwining sensuous and divine love."

Once you understand this concept of "intertwining" of different but still related ideas, where seemingly competing rhythmic schemes (shorter, highly syncopated patterns running against augmented, slower-moving lines) accompany multiple, concurrently-sung melodies and texts, the musical construct begins to make sense. The connection between this work and Machaut's Messe de Nostre Dame, with which it was designed to be performed, demands a different level of listening and understanding that some listeners will appreciate and others will choose to ignore. However you listen, your efforts to follow the music are made easier because of O'Regan's neatly devised voicings that allow us to hear everything, no matter how complex the texture.

And of course, we couldn't ask for better interpreters: the Orlando Consort and Estonian Philharmonic Chamber Choir have long experience in performing the most challenging music, from the most obscure early manuscripts to recently commissioned works. I found Part III of Scattered Rhymes the most fascinating and memorable. Here, O'Regan attempts to examine Machaut's "harmonic process" by breaking down his structures into smaller pieces, moving the harmonic rhythm more slowly, building from an insistent, pulsing open fifth and adding and subtracting pitches, harmonies, and melodies. It's an exciting effect that compels repeated hearing--and this section certainly could stand on its own on a concert program.

Machaut's Mass is extremely important for historical reasons, but it's not one of the more popular or accessible pre-Renaissance works, not only because it's difficult to sing, but also owing to its stark, strange sound, odd dissonances, and textures that shift from spare to highly ornamented, leaving listeners to find a context for this often puzzling music, remembering, of course, that it was never designed as a concert piece! Again, the four voices of the Orlando Consort bring vibrant energy and ear-pleasing resonance to this ancient, unusual masterpiece--and continue through the rest of the program, four more works that are well-chosen to balance the weightier first half of the disc. And before this does turn into an article, I'll end by urging anyone interested in a consistently engaging, musically challenging, and aesthetically rewarding experience to delay no longer: get this disc! [4/21/2008]

--David Vernier