Wednesday, October 07, 2020

Singing Upon the Book: Further Methods of Chant Harmonization (Part 1)

At the beginning of the year, we printed an article by Mr Joseph Ahmad, who works as a researcher at the École Biblique et Archéologique Française in Jerusalem, on the use of the “ison” or drone in Gregorian chant. We are happy to share this follow-up, which will be presented in two parts, with our renewed thanks to the author.

In my previous post, I discussed the most basic form of what medieval music theorists called diaphonia, namely the ison also known as diaphonia basilica. In this post, I would like to discuss some other forms of chant harmonization that choristers could employ for a given piece of chant in times past. Though these are more difficult, the ison can function as a gateway to these other forms, since, over time, it trains one’s ability to detect and produce chords. That is, one will develop sense of how different intervals “feel,” especially the perfect fifth, perfect fourth, and octave. Once you have a “feel” for these intervals—as well as comfort with sight reading neumes—you can begin experimenting with the methods discussed below.
Book of Hours, Paris 1450 - c. 14 British Library MS Harley 2971 f. 109v
Before we get to the music, I would like to consider a possible pitfall in these forms of ornamentation or enhancement that has plagued singers over history. How much is too much? How do we avoid mere aestheticism? It depends on how one builds upon a given piece of chant. To use a metaphor, is the manner in which you “diaphonize” akin to to donning a horse with horseshoes or garlands? In the former case, the addition enhances what is already an essential characteristic. The horseshoe helps the horse do horsy things. The latter case is an aesthetic fancy or a piece of buffoonery—unless, of course, this horse is a Hindu god. In the “garland approach,” sacred music becomes less and less mystagogic and iconographic, favoring that which is theatrical, entertaining, and aesthetically immanent—or, in the words of the Oxford Companion to Music, “meretricious and unliturgical.” The “horseshoe approach” consists of musically explaining or enhancing the pre-existing text, preserving the musical iconography and mystagogic nature of the original chant. As an example, I’d contend that a piece like Victoria’s Missa pro defunctis enhances, whereas a piece like Mozart’s Requiem, though brilliant as a musical composition, obscures. So, as you look at the following techniques, use your judgment and strive for the horseshoe approach.
Parallel Organum
Parallel organum, singing parallel fourths and fifths from the melody, is the earliest mentioned form of harmonization. Some form of it is arguably implied in Ordo Romanus XXX (ca. 8th c.), wherein the author calls a certain class of singers paraphonistae. In Greek musical terminology, the symphoniai paraphoniai designated consonances at the fourth and the fifth, as opposed to the symphoniai antiphonai, which designated tones either at unison or the octave. Thus it would seem that the paraphonistae were responsible for singing harmony.
This was not necessarily revolutionary, and perhaps such diaphonia was older in Greco-Roman music, for harmonizing in fourths and fifths seems prevalent in folk music around the world. Consider examples from South Africa:
and the Anglo-American tradition of sacred harp singing ().
In turn, some of these, like sacred harp singing and the Icelandic rímur, may actually be folk adaptations of Medieval church singing.
Parallel organum is discussed clearly in the anonymous Musica Enchiriadis and Guido d’Arezzo’s Micrologus. For two voices, the Musica Enchiriadis prefers parallel fourths; for three voices, it places one voice a 4th above and another a 5th below the melody. Guido has the reverse. One can set additional voices an octave apart from any of these three voices. Thus to these three initial voices, we can add a fourth that sings the written chant an octave higher than the principal voice.
Parallel Organum Demonstrated in the Musica Enchiriadis (British Library Add MS 17808, f. 39v)
If the number and arrangement of singers is flexible, the parallelism itself is likewise flexible. After describing strict parallel organum, Guido further describes a variation that he prefers, which seems to be a mixture of parallel organum and droning, whereby one remains within a 4th below the principal voice, but the organal voice never drops below Do. This example ( of organum from the Musica Enchiriadis seems to use a similar technique.
One can also break up strict parallelism by transitioning to the octave (or unison) at certain points, usually at the beginning and end of a phrase. You can hear this in this performance of the Advent Introit Rorate Caeli:
as well as in this performance of the Christmas day Introit Puer Natus Est .
During the Renaissance, this semi-parallel organum was sometimes called the Gymel (“twin”), though employing the third and the sixth in accord with the tastes of the period.
A further variation is to incorporate a drone, as in this performance of Kyrie IV.
In general, one of the easiest places to practice your skills in parallel organum is with psalm tones, given their limited movement. For the Office or parts of the Mass like the Introit, drone during the antiphon and then try to follow the verse in parallel.
Florid Organum
The polyphony developed at Notre-Dame de Paris in the 12th–13th centuries, particularly by the composers Leoninus and Perotinus, was a major advance in the development of harmony. The vast majority of pieces composed in this style can be found in the Magnus Liber Organi, which contains chant settings for the whole liturgical year. One genre of polyphony developed at Notre Dame is called florid organum (see this as an example.)
Though impressive and virtuosic, its basic structure is quite straightforward. For a given piece of chant, treat the written notes as a series of drones. This is the cantus firmus. Over this cantus firmus one or more cantors improvise a melody. At the cantor’s signal, the droning voices move to the next note of the notated chant. Beforehand, the cantor should note the intervals at which he would like to meet each drone in a given piece of chant (usually unison, the fifth, or the octave). After agreeing on a starting interval, the cantor intones the chant, followed by the drones. This is all demonstrated quite clearly in this video:
A leaf from the Magnus Liber Organi (hosted at
Further examples of improvised florid organum: this video demonstrates the technique with a single cantor;
this video is a good demonstration of more complex various forms of florid organum. Note also how the cantor communicates to the other singers; they are following this piece of chant:
Certainly this sort of organum has a great deal of expressive potential, especially if you have soulful cantors who are able and willing to navigate all the musical nooks and crannies of a given piece of chant. But when would it be practical to use in the liturgy? Given the flexibility with which the cantor(s) can extend or shorten the length of a piece of chant when sung in this way, it would seem quite sensible to use this style of organum during processions (such as a procession at the Alleluia) or other events of varying length (like communion).
Finally, a word of caution from John of Salisbury. Done artlessly, this form of organum can be tedious and esoteric. The venerable bishop worried that florid organum would be “more fitted to excite lust than devotion”; but, he continues, “if it is kept in the limits of moderation, it drives away care from the soul and the solicitudes of life, confers joy and peace and exultation in God, and transports the soul to the society of angels.”

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