The text of Dufay’s large-scale motet for the dedication of the cathedral, Nuper rosarum flores, is probably by the composer himself, and draws attention to the golden rose, bestowed on the city by the Pope as a sign of favour, and prominently displayed on the cathedral altar. The second stanza addresses Pope Eugene by name. The final two stanzas turn to the Virgin Mary, dedicatee of the cathedral, and offer a plea for her help in gaining forgiveness for sins.

Dufay’s motet has sparked discussion about the relation of its dimensions to architectural elements of the new cathedral. The work has a clear formal design with eight segments based on the alternation of high-voice duets with full-voice sections. This progression of duet–tutti sections creates the effect of increasing speed as the duration of the breve in each statement decreases from six units to four to two, and then broadens out to three in the final section. The proportion of 6:4:2:3 has been the focus of studies that seek to relate the motet’s temporal dimensions to those of the cathedral—or to its prototype, the Temple of Solomon. Other commentators urge caution in interpreting numerical evidence.

In Nuper rosarum flores the two high voices sing all four stanzas of text, while the lower two sing a different text, ‘Terribilis est locus iste’ (‘Awe-inspiring is this place’), appropriately derived from the opening words of the introit chant at the Mass for the dedication of a church. The complete text of the introit quotes the words of Jacob (Genesis 28: 17). In a dream, he sees a ladder leading up to heaven, where God speaks and promises to bless him and his descendants. Upon awakening, Jacob exclaims: ‘Awe-inspiring is this place. This is no other but the house of God and the gate of heaven.’ The two low voices each sing the chant at different pitch levels a fifth apart in a kind of free canon. They state the same music four times during the motet, mostly in long notes that create a strong underpinning for the work. The upper voices, by contrast, introduce the motet with a lyrical duet that floats upward, then gains rhythmic momentum. This opening duet has a duration of twenty-eight breves (modern bars), and the full-voiced section that follows also spans twenty-eight breves.

The number twenty-eight is conspicuous in Nuper rosarum flores, and various aspects of its appearance have been related to modular elements of the cathedral. The twenty-eight-bar segments appear to reflect the measurements of a central aspect of the new cathedral. Brunelleschi’s massive dome rests on the sturdy walls of an octagonal drum. The horizontal length of each inner wall of the drum is twenty-eight braccia (arm-lengths, a Florentine unit measuring about two feet). Dufay’s motet has eight sections, and each of these has a duration of twenty-eight breves. The number further appears in the twenty-eight lines of the main text, as well as the fourteen notes of the chant melody in each of the two lower voices (14x2). Those sitting under Brunelleschi’s dome during the dedication could see the eight walls of the drum, as well as hear the eight distinct sections in Dufay’s motet. It would be a simple matter to spread word that the motet evoked the module of twenty-eight braccia for the octagonal drum that supports the dome.

from notes by Patrick Macey © 2022