Into which of those categories might the Credo quarti toni fall? This piece survives by the skin of its teeth, in a single manuscript in Cambrai copied around the time of Josquin’s death. Some authorities have questioned Josquin’s authorship on the grounds that the piece was so little circulated; but Josquin did have links with Cambrai stretching back to his childhood, and the manuscript firmly ascribes this work to ‘Jossequin des Prez’. Moreover it has been copied in the company of two Masses securely by Josquin, the Missa Gaudeamus, which features earlier in the manuscript, and the Missa De beata virgine, which is placed directly before the Credo, again attributed to ‘Jossequin des Prez’. On these grounds, Josquin’s claim to the Credo quarti toni really ought to be taken seriously. But what of its musical content?
Some experts reckon the piece to be stylistically uncharacteristic. Matters change, however, when it is viewed from the perspective of how it was made. Its composer has taken one of the most familiar of all medieval melodies, the plainchant formula commonly used to sing the words of the Creed, and has miraculously converted this tune into a tight canon for tenor and baritone. Both voices sing the outline contours of the chant, but they start on different notes – the tenor a fifth higher than the baritone – and at slightly different times. To accompany them, the composer has added two superb outer voices, an alto and a bass, both of which move athletically through exceptionally wide ranges, sometimes singing very low, elsewhere very high. Although the four voices perform together for much of the time, in places the canon falls silent, leaving the alto and bass to cavort on their own. And elsewhere it is the outer voices that take a rest, the texture reducing to its conceptual backbone of chant-based canon.
This work does possess a context of sorts. Two other Josquin Masses, the Missa Sine nomine and the Missa De beata virgine, also have canonic Creeds based on this plainchant melody; so it would seem that Josquin tackled the same challenge three times over, arriving at three different solutions. Moreover the Creeds of the Missa Sine nomine and the Missa De beata virgine sometimes sound remarkably similar to the Credo quarti toni, raising the possibility that the Cambrai setting was a prototype that the later Masses later cannibalized. In the Cambrai manuscript the Credo quarti toni is copied immediately after the Missa De beata virgine. Might Josquin therefore have drafted it to be part of that Mass, but quickly rejected it, composing instead the five-voice setting that then became standard? The theory has its appeal; but as so often with Josquin, we may never know the truth.
from notes by John Milsom © 2011