Missa prolationum

The Missa prolationum is a musical setting of the Ordinary of the Mass, by Johannes Ockeghem, dating from the second half of the 15th century. Based on freely written material probably composed by Ockeghem himself, and consisting entirely of mensuration canonsJohannes Ockeghem, "Masses and Mass Sections IX-XVI." Ed. D. Plamenac. Publikationen älterer Musik, ii (New York, 1947, 2/1966)., it has been called "perhaps the most extraordinary contrapuntal achievement of the fifteenth century", and was possibly the first multi-part work to be written which used a unifying canonic principle all its movements.Perkins, Grove (1980)Lockwood/Kirkman, "Mass", Grove online
==Music==
The mass is for four voices, and is in the usual parts:
# Kyrie
# Gloria
# Credo
# Sanctus and Benedictus
# Agnus Dei (in three sections: I, II, III)
A typical performance takes 30 to 35 minutes.
The mass uses progressive canon through all its movements, similar to the way J.S. Bach used canon in the canonic movements of the Goldberg Variations more than two centuries later. Most of the movements feature pairs of mensuration canons. The interval separating the two voices singing each canon grows successively in each consecutive movement, beginning on the unison, proceeding next to the second, then the third, and so forth, reaching the octave in the Sanctus at the "Osanna" section. The four voices each sing in a different mensuration, so rendered in modern music notation, the four voices in the Kyrie II sing respectively in the meters 2/2, 3/2, 9/4, and 6/4, with the voices singing canon 1 in 2/2 and 3/2 (the voice in 3/2 sings the tune half again as slowly, so the voices pull apart gradually), and the voices singing canon 2 in 9/4 and 6/4, again with the voice in 9/4 singing half again as slowly, pulling away from the 6/4 voice. In the score, only one voice was written out for each canon, with the mensuration marks (approximately equivalent to a modern time signature) given alongside, so the singers would understand that they are to sing in those proportions, and thus at different speeds; in addition the intervals between the voices are given in the score by the positions of the C clefs. What so astonished musicians and listeners from Ockeghem's age to the present day is that he was able to accomplish the extraordinarily difficult feat of getting it all to work out.Atlas, p. 153-4
Ockeghem was the first composer to write canons using the intervals of the second, third, sixth, and seventh, the "imperfect" intervals, and the Missa prolationum may have been the first work to employ them. The layout of the work, with the interval of imitation expanding from the unison up to the octave, is the same as that used by J.S. Bach in the Goldberg Variations; it is not known, however, if Bach was familiar with Ockeghem's work (which was generally unavailable in the 18th century).Mann/Wilson/Urquhart, Canon, Grove online Another unusual feature of this mass is that the tunes used for its canons were all apparently freely composed; none have been identified from other sources. During this period of musical history, most of the time composers built masses on pre-existing tunes, such as Gregorian chant or even popular songs.
==Source and dating==
There are two sources preserving the mass. One is the Chigi Codex (f.106v to 114r), which was copied for Philip I of Castile sometime between 1498 and 1503, shortly after Ockeghem's death. The other one is the Vienna manuscript (Wien, Österreichische Nationalbibliothek, Handschriftensammlung, MS 11883, f.208r to 221r). Exactly when he wrote the Missa prolationum is not known, and there is no evidence to allow its dating other than what can be inferred from its internal characteristics, or from a comparison with other works of Ockeghem which already have tentative dates (Ockeghem's output is notoriously resistant to precise dating, even for a composer of the Renaissance; not only did he have an unusually long career, possibly spanning sixty active years as a composer, but there are few records tying specific pieces to events). No dates more precise than "mid-15th century" or "second half of 15th century" have been established for this piece.Mann/Wilson/Urquhart, Canon, Grove online
==References==
* Leeman Perkins, "Johannes Ockeghem." The New Grove Dictionary of Music and Musicians, ed. Stanley Sadie. London, Macmillan, 1980. (20 vol.) ISBN 1-56159-174-2.
* Leeman Perkins, "Johannes Ockeghem." Grove Music Online, ed. L. Macy (Accessed July 31, 2007), (subscription access)
* Alfred Mann, J. Kenneth Wilson, Peter Urquhart, "Canon." Grove Music Online, ed. L. Macy (Accessed July 31, 2007), (subscription access)
* Lewis Lockwood, Andrew Kirkman, "Mass." Grove Music Online, ed. L. Macy (Accessed July 31, 2007), (subscription access)
* Allan W. Atlas, Renaissance Music: Music in Western Europe, 1400–1600. New York, W.W. Norton & Co., 1998. ISBN 0-393-97169-4
==Notes==
Category:Compositions by Johannes Ockeghem
Category:Renaissance music
Category:Masses (music)