Gregorian Rhythm Wars contains all previous installments of our series.
Please refer to our Chant Glossary for definitions of unfamiliar terms.
N HIS NOVEMBER 10 guest post, Matthew Frederes mentions, among other supposed defects in the rendition of chant, what he refers to as pulsation. I assume he means what is more typically known as repercussion or rearticulation. It is most instructive to read what the Solesmes “Rules for Interpretation” say on the matter:
Formerly each of these two or three notes [of the distropha or tristropha] was characterised by a slight stress or impulse of the voice; in practice, we advise the joining of the notes in one sound. These double or triple notes, especially when repeated, may be sung with a slight crescendo or decrescendo according to their position in the word of the text or in the melodic line. A gentle and delicate repercussion (i.e. a fresh layer of sound) is needed at the beginning of each distropha or tristropha, as well as on the ﬁrst note of any group which begins on the same degree as the strophicus. (Liber Usualis, xxiij; Liber Brevior, xxj)
This paragraph contains a rather frank admission that the Solesmes method practice of tying repeated notes together and fusing them into a single sound of double or triple length is a departure from the historic manner of singing (here I repeat my own wording from a one-page handout on the topic). The preface to the Vatican edition merely says that such notes “must be sustained for a length of time in proportion to their number” and that the pressus “should be sung with more intensity, or even, if it be preferred, tremolo [‘tremula voce’ in the Latin version].”
Differentiation • I would argue that, in the oldest sources, a tristropha with the rhythm short-short-long and a bivirga with the rhythm long-long have exactly the same duration. They are not used interchangeably; without repercussion or some other difference in their rendition, however, they would be indistinguishable except on paper. Almost ironically, according to the Solesmes method, the tristropha, interpreted as three short notes all tied together, and the bivirga with horizonatal episema, interpreted as two long notes tied together, each approximately 1.5 times the short value, also both have the same duration as each other and, without repercussion, sound exactly the same. Several examples of the bivirga with episema can be found in the Tenebrae responsories. The modern notation edition of the Liber Usualis writes two eighth notes tied together, each with an episema.
Sources • I would also like to address Jeff Ostrowski’s Eripe me alleluia example from his post titled “How Does the Official Rhythm Actually Sound?” There he discussed the morae vocis indicated by the note spacing of the Vatican edition, with a comparison of the Solesmes rhythm. His observations are accurate but do not go far enough. Where do those morae vocis actually come from? He has asked me twice not to use “Because Dom Cardine says so” as an argument—which I wouldn’t do anyway. Now I ask in return: give us something more substantial than “Because the Vatican edition says so”! Why did the editors put the spaces there? Here is a duplex rhythmic example incorporating the melodic corrections:
And another without them:
The St. Gall neumes are reproduced from the Graduale Restitutum of Anton Stingl jun. (Gregor und Taube).