The source on which the cantus firmus of the Caput Masses by Dufay, Ockeghem, and Obrecht is based is the melodic variant of the melisma on the final word "caput" from the antiphon Venit ad Petrum of the Sarum use. English influence on the earliest Mass (still considered Dufay's) can be seen in its use of the Kyrie trope Deus creator omnium, a melody appearing almost invariably in troped Sarum Graduals. The fact that the Sarum Processionals have not been reprinted with their music may be the reason why the source of the caput melody has remained undiscovered for so long. It appears, however, in the facsimile edition of the Graduale Sarisburiense since 1894. Dufay's tenor corresponds to the caput melisma except for two notes and the arrangement of the ligatures. This is important for the comparison with Ockeghem's and Obrecht's Caput masses, since they take over not only the exact rhythmic layout of Dufay's cantus firmus, but often its major divisions by rests as well. Therefore Ockeghem and Obrecht must have used the mass of their predecessor as a model and springboard. Van den Borren's hypothesis that Ockeghem's mass might be the earliest one of the three cannot be true, since it omits the first part of the cantus firmus in the Christe and "since it is most unlikely that partial presentation should precede integral presentation." Ockeghem follows the model more closely than Obrecht. While the former borrows the arrangement of the ligatures and quotes the cantus firmus in the tenor voice only, Obrecht treats it more freely, shifting it to other voices and transposing it between the movements.

Works: Dufay: Missa Caput (256-66); Ockeghem: Missa Caput (263-69); Obrecht: Missa Caput (264-65, 269-71).

Sources: Antiphon: Venit ad Petrum (242-49); Dufay: Missa Caput (263-71).

Index Classifications: 1400s

Contributed by: Andreas Giger