Magnificat

After its opening verse, Monteverdi’s 1610 setting of Dixit Dominus alternates between falsobordone settings of the chant (tone 4 with finalis e) and imitative textures built over the cantus firmus in the bass. Each falsobordone is followed by an instrumental ritornello. The doxology then concludes with a solo tenor intonation of the psalm tone and a six-voice polyphonic chorus, balancing the opening verse in symmetrical construction. Throughout the psalm, only the melismas that conclude each half verse (typical for falsobordoni) and the ritornellos are free of the chant.

Within this scheme, Monteverdi varies the context of the chant in several different ways. In the falsobordoni themselves, the first half-verse is presented on an a minor chord (A major for verse 6), while the second half-verse is a steplower on a G major triad. In the alternate verses 3, 5, and 7, the chant, transferred to the bass in half and quarter notes, supports first an imitative duet, and finally an imitative five-voice texture, creating a series of variations over the bass cantus firmus. The beginning of this latter verse looks very much like measured falsobordone and illustrates how closely chordal textures in the harmonization of a psalm tone approximate falsobordone, expecially when the chant is in the bass, allowing for very little variety of harmonization.

Even within each of these verse the principle of variation predominates, since each half verse repeats the text, prompting variation in its setting. For example the third verse (Virgam virtutis) begins with the cantus alone and then adding the sextus in an imitative texture for the reiteration of the text. Note that although the chant is not present for the first statement of the half verse in the cantus, the bassus generalis still reflects the psalm tone. In the second half-verse of the verse a subtle coloristic variation is achieved by shifting the leading role from cantus to the sextus.

Even in those passages not based on the cantus firmus the principle of variation prevails. The melismas concluding each half-verse are rhythmic variants of a single underlying descending sequence. Each instrumental ritornello is similarly a slightly modified repetition (transposed up a step) of the immediately preceding melisma, exchanging the vocal sonority for an instrumental one.

The first verse and the doxology exhibit yet further contextual variants for the cantus firmus. In the first verse, the psalm tone itself becomes a subject for polyphonic imitation, joined by a countersubject in a six-voice texture. At the beginning of the doxology the solo cantus firmus appears in long notes a step lower on g in cantus mollis (one flat). The Sicut erat is unrelated to the first verse of the psalm, but is reminiscent in its reiteration of the sustained psalm tone on D (harmonized with D minor) of the Domine ad adiuvandum respond that opened the Vespers.

[Adapted from The Monteverdi Vespers of 1610: Music, Context, Performance by Jeffrey Kurtzman. Oxford and New York: Oxford University Press, 1999, pp 211-215.]