Missa De plus en plus: Agnus Dei
Johannes Ockeghem (ca. 1420-1497)
Norton Recorded Anthology of Western Music, CD 2 Tracks 31-32
Mr. Ockeghem's generation knew how to write well organized music without sounding well organized. This, to my ears, is where good music can be found. The art of writing music, a step taken after improvisation, presents the challenge of musical structure. The trick, of course, is to find a way to put things together that encourages the listener to hear the piece more than once. If the musical structure is obvious the piece runs the risk of being plebeian. If it is obtuse the listener may become disengaged. The solution employed here, the use of cantus firmus, is a likable solution because it provides a wealth of form and contour without being obvious.
If Mr. Ockeghem had chosen the cantus instead of the tenor from Binchois' rondeau, the admirable and memorable contour of that line would have shaped this piece differently. The cantus firmus of this mass has an unremarkable contour. And this unremarkable charateristic is taken advantage of, particularly in this Agnus Dei. Because the cantus firmus does not exploit any register more than another, the result, when set in the four-voiced texture of the mass, is the large, square sonorities that are so appealing in religious efforts.
What I like about this Agnus Dei is the use of rests. Because of the rests, we do enjoy some contrast of register in this piece. More importantly, the rests create a foreground and background. Simply by taking turns, the voices can guide the listener's ear through these elegantly tangled lines.