Claudio Campesato · Original article in Italian · Español · 10 November 2026
In the cloister of Sant’Anselmo, on Rome’s Aventine Hill, the noticeboards of the university stand alongside those of the monastic college. Among the notices about academic life, you may therefore come across announcements of a very different kind.
Like this one:
“From this evening, we will no longer sing the psalmody to tone 5a2: it will be sung to tone 5a, that is, without B-flat.
This does not concern the antiphons, but only the psalmody.”
The notice is accompanied by a drawing of a smiling monk, singing with a book in one hand and a finger raised. Next to him is a crossed-out flat, like a no-parking sign: the flat may no longer pass this way.
Anyone who sings from the Antiphonale monasticum will have understood at once. For everyone else, “5a2” might be the number of a classroom, a temporary password or, for lovers of liturgical sources, the incomplete shelfmark of a manuscript.
In fact, it is a musical indication.
What happened to B-flat?
In monastic prayer, psalms are often sung to melodic formulas called psalm tones. These are short musical patterns that adapt to the words of the verses: the voice moves along on one note, pauses halfway, resumes and comes to a close. In the words of a thirteenth-century Dominican, Jerome of Moravia: “Quintus tonus sic incipit et sic flectitur, et sic mediatur, et sic finitur.” “The fifth tone begins like this, bends like this, reaches its midpoint like this, and ends like this.”
The psalm is normally accompanied by an antiphon, a short chant that introduces and closes it. The psalm tone is usually chosen according to the mode of the antiphon; its final cadence also takes account of the melody of the antiphon, which is repeated after the psalm or canticle.
Let us take a concrete example. At Vespers on Corpus Christi the antiphon O sacrum convivium accompanies the Magnificat, Mary’s canticle: first the antiphon is sung, then the canticle and finally the antiphon is repeated.
Beside the beginning of the antiphon we find our indication: 5a2. The 5 denotes the fifth tone; the a indicates the note on which the ending finishes, A; the 2 distinguishes a second formula that reaches the same note by a different route.
At the end of the score, a few notes appear above the vowels E-u-o-u-a-e: these are the vowels of the Latin words saeculorum. Amen, “of ages. Amen”. They show the ending of the psalm tone through the conclusion of the doxology that follows the canticle.
The difference between the two formulas concerns a B: B-natural in 5a, B-flat in 5a2. There is only a semitone between them, but that is enough to change the colour of the ending. And when singing together, it helps if everyone takes the same path!
The new Antiphonale monasticum of Solesmes, published from 2005 onwards, offers these two possibilities. In his introduction to the new antiphonary, Dom Daniel Saulnier explains that the formula with the flat revives a practice attested in numerous medieval manuscripts, especially in the Germanic tradition. The choice between the two endings depends on the melody of the antiphon: O sacrum convivium is one of the examples he mentions.
Saulnier observes that the difference arises from the relationship with the antiphon. He acknowledges, however, that some communities may find it difficult to sing the nuance together. In that case, they can continue to use the formula with B-natural throughout. This is the solution announced for Sant’Anselmo in the notice.
Naturally, B-flat has not been banished from the whole monastery. The notice takes care to make this clear: the decision concerns the psalmody; the antiphons keep their melody, flats and all.
We can imagine the relief of a flat which, having read to the end, discovered that it had not been sent out of the cloister: in the antiphons it may stay where it belongs.
A medieval prohibition
Speaking of prohibitions, an anonymous twelfth-century Cistercian author addressed the question of b rotundum, the sign from which our flat derives. In the treatise on the correction of the antiphonary, he wrote:
Nullus enim cantus qui sine ipso notari potest, per ipsum notari debet.
“No chant that can be notated without it should be notated with it.” In other words, if the flat is not needed, it is better to leave it out.
But the author did not exclude it in every case: he explained that it had been introduced ad servandam in plerisque cantibus euphoniam, “to preserve a pleasing sound in many chants”. The rule concerned notation and the organisation of melodies in a context different from the choice between the two endings in our notice. It does show, however, how long singers have reflected on that little sign.
The disobedient canonesses
This little Roman notice brought to mind another B-flat, much older and of a very different kind, and a community about which Professor Franz Karl Praßl often spoke in class: the canonesses of Klosterneuburg, in Austria. He also remembered them for a certain musical “disobedience”.
What had they done?
In the twelfth century these women prayed and sang from liturgical books of their own. Among the surviving manuscripts are the Klosterneuburg antiphonaries, which scholars have associated with the women’s community.
In the responsory Fuerunt sine querela — “They were blameless” — a chant in the second mode for the Common of Apostles, a small b written in the manuscript has been interpreted by scholars as an indication of a low B-flat.
This is an exceptionally rare note in that position, outside the musical gamut normally taught in medieval schools. And yet its sign is there, in the book.
We do not know whether the person who wrote it meant to correct a theorist. We do know, however, that these manuscripts preserve a distinctive liturgical voice, shaped in part by small musical choices.
And in Toledo?
In 1565 the Dominican theorist Tomás de Santa María, who wrote chiefly for organists, explained in his Arte de tañer fantasía, published in Valladolid, that the fifth tone is by nature sung and played with B-flat, whereas its seculorum (the psalm-tone formula associated with the tone, whose name recalls the saeculorum. Amen of the Gloria Patri) is sung and played with B-natural. The distinction, though made in a different context, recalls the one in our notice. But he added an exception: “aunque en el Arçobispado de toledo, tambien el seculorum se canta por Bemol”, that is, “although in the archdiocese of Toledo the seculorum too is sung with B-flat”. There, in short, our flat would have found a somewhat warmer welcome.
For some, perhaps, all these reflections on such a small sign may seem like trifles. But for those bound to the choir — yesterday as today — even a B-natural or a B-flat can become a very serious matter. When the psalms are sung together, day after day, such a small note can certainly make itself noticed!
After all, as everyone knows, prohibitions stir curiosity.
Cover image: AI-generated adaptation based on the photograph Interior Courtyards at Sant’Anselmo by ElijahOwens, Wikimedia Commons, CC BY-SA 4.0. The image is an illustrative reconstruction, shared under the same licence.
