This is the second part of the article by Mr Joseph Ahmad which was published yesterday, with our thanks.
Discantus and Cantare Super Librum
From the 12th or 13th centuries up to the 19th century, there persisted a tradition of improvising contrapuntal polyphonic settings of chant, variously called discantus, cantare super librum, faburden, chanter sur le livre, sortisatio, and contrapunto alla mente, depending on the period and region. Moreover, it admitted of many different genres, ranging from the aformentioned gymel—which is close to parallel organum—to canons, to fully independent four voice polyphony akin to a high quality written composition. Likewise, church records and witnesses, whether praising or decrying the practice, testify to its spread all across Europe.
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| Johannes Ockeghem (front right) and his choir in the chapel of King Charles VII of France. |
Regarding the quality of cantare super librum heard at the Sistine Chapel, Antimo Liberati observed in 1666, “listening to each of these erudite singers while they compose extemporaneously upon the plainchant, that is, when they make contrappunto alla mente with noble harmony as if it were written down and composed in advance, provokes at the same time wonder and sweetness.”
The Oxford Companion to Music records two later witnesses to such sophisticated improvisation. “Padre Martini, in his great work on counterpoint, says that in 1747 he heard very perfect extemporaneous singing in four parts in the church of St. John Lateran at Rome, and Dr. Burney…affirms (ca. 18050, ‘There are musicians in the church so well versed in this kind of singing that they lead off, and even carry on, fugues extempore when the subject will allow it, without confounding or encroaching on the other parts or committing a single fault in the harmony.’ ” Writing in 1938, the author of the Companion dryly comments, “despite the respectable authority of the writer, [this] is scarcely credible to us today.” If only he knew.
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| Chant book commissioned for the Sistine Chapel, ca. 1520 (Capp. Sist. 10, fol. 2v) |
Still, given the difficulty of such a group improvisation, the results were sometimes cacophonous. In the early 19th century Adrien de La Fage lamented, “France…has never abandoned its mania of improvising on a plainsong…and if today the combat has come to an end, it is only for lack of contestants. I say ‘combat,’ and with good reason; for it was indeed a perpetual battle, in which all the combatants appeared to butcher each other. The cathedral chancels were real battlefields, where one heard the cantors droning hoarsely in their lower register, then the counter-tenors shouting at the top of their lungs, and the tenors fitting in as best they could. For this, all these good men had no rule other than habit: they tried to start off on one of the notes of the harmony, and, for the rest, they abandoned themselves to Providence.”
Thus, one can only conclude that he should aspire to be more like the choristers of the Sistine Chapel and the Lateran, rather than the French.
The basic principle is quite simple. One portion of the choir sings a given piece of plainchant it in a very slow and measured manner (e.g., 4 beats per written neume). Usually this is done by the bass, but any other part can do it as well. Around this cantus firmus the other voices improvise melodies, following certain prescribed formulae. These formulae determine the intervals from which other voices sing above and below the cantus firmus, and they determine certain rules for cadences at the ends of phrases. In addition to following these formulae, singers add ornamentation.
For example, in discantus simplex, one voice sings the cantus firmus while the second voice, moving contrariwise to the cantus firmus, proceeds from unison, to the third, the fifth, the octave, and then back to the fifth, the third, and unison, cycling through this pattern throughout the piece. The discanting voice can add diminutions to this basic pattern, and a third voice can sing in parallel fifths with the cantus firmus to enrich the sound. If I am not mistaken, Jerycho’s performance of Kyrie IX employs a similar technique.
Another example of a simple formula is the fauxbourdon.
One voice (usually a tenor or bass) sings the chant as written, forming a cantus firmus. Another voice sings a gymel in thirds above the tenor—that is, he sings parallel thirds, transitioning to the octave or unison at certain points, usually the beginning and ending of phrases. A third voice sings a gymel above the cantus firmus alternating between fifths and sixths, never singing two fifths in a row. Finally a fourth voice either sings the cantus firmus an octave lower or a gymel in lower thirds beneath the cantus firmus. The English style fauxbourdon places the cantus firmus in the topmost voice.
There are further rules about cadences and ornamentation that are explained in the tutorial.
Regarding this rich and diverse tradition, I would like to direct you to a number of resources where you can see different techniques demonstrated. On the earlier side, discussing practices of the 14th century, see this lecture by Dr. Niels Berentsen.
For Cantare Super Librum in the Renaissance, see the excellent tutorials by Dr. Barnabé Janin, such as the ones linked above, and those by Dr. Peter Schubert such as this one:
Dr. Janin has also written a very practical guide for singers: Chanter sur le livre Manuel pratique d’improvisation polyphonique de la Renaissance: https://symetrie.com/fr/titres/chanter-sur-le-livre.
Finally, for a late example of chanter sur le livre as it might have sounded in the 19th century, see this video by the Chantres du Thoronet.
I hope that with this overview, you have gotten a taste of the different ways chant was sung throughout the Church’s history. Now, as Janin says at the end of his tutorials, à vous jouer!
