At the approach of his 600^th birthday, Johannes Ockeghem (ca. 1420-1497) thrives, thanks in great measure to director Scott Metcalfe and the singers of Blue Heron, who have undertaken to present his complete works in a series of 13 programs spread over seven seasons from 2015 to 2021. Concert 8, centered on the four-voice Missa cuiusvis toni (Mass on whatever tone you please), was performed at St. Cecilia Parish, Boston, on Thursday, October 11^th, and again at the First Church in Cambridge, Congregational, on Saturday, October 13^th. A review of Thursday’s concert follows.

Born in the French-speaking province of Hainaut in what is now Belgium, Ockeghem served the French court as singer-composer for most of his career. Hailed by his contemporary, the composer and theorist Johannes Tinctoris, as “the first among the most excellent masters of his age” and lamented at his death by both musicians and poets, not long afterwards most of his music was no longer current. 16^th-and 17^th-century critics remembered — and censured — him for the “arid complexity” and “contrapuntal artifice” of musical puzzles like the Missa cuiusvis toni, the Missa prolationum, and the canonic song “Prenez sur moi.” Without proper understanding of 15^th-century notation, Enlightenment historians such as J.S. Bach’s biographer Johann Forkel found Ockeghem’s music clumsy and awkward. German scholars of the 1920s and 1930s, provided with improved transcriptions, held it to be devoid of rational structure while imbued with northern European mysticism, a view that has persisted in textbooks to this day.

In his informative notes, along with a welcome live demonstration, Scott Metcalfe explained the meaning of cuiusvis toni (on whatever tone you please) in terms of the different scale patterns of whole and half steps that result from singing on the solmisation syllables ut (do), re, or mi (familiar to those trained on the English “movable do ” but not those used to the French “fixed do). The three possible modes could also be thought of as scales built on C, D and E, using only the white notes of a piano. Blue Heron’s singers obliged with chant examples on D re, C ut, and E mi, followed by a hilarious rendition of “Happy Birthday Johannes” in each of the three modes.

The concert began with a motet for six voices transmitted only in the “Chigi Codex,” the magnificently illuminated manuscript in choirbook form that is also one of the principal sources of the Missa cuiusvis toni. Although the motet’s composer is not named, it may possibly be a work by Ockeghem’s contemporary Johannes Regis. Its rich musical texture featured a tenor cantus firmus derived from a Marian antiphon, sung in canon by Jason McStoots and Stefan Reed, against sinuous counterpoint in the other four parts. The text of the two upper parts, sung by soprano Margot Rood, cantus, and Owen McIntosh, contratenor, included multiple stanzas of a rhymed sequence, with basses Paul Guttry and David McFerrin delivering a much shorter text based on another Marian antiphon. While the simultaneous performance of all three texts made it difficult to follow any single one of them in the echoing space of the St. Cecilia church, in a smaller and less reverberant space the complementary texts might have enriched the celebration of the Purification of the Virgin Mary for singers and clerical participants alike. As it was, the performance was stunning, the upper voices floating above the tenors and basses in an intricate but always sensitively balanced sound complex.

Metcalfe distributed the Mass over the two halves, giving us a taste of the varied harmonies and cadential adjustments in the four parts depending on their realization on ut, re, or mi. The Kyrie, with its 3 x 3 invocations, was sung by two four-voice teams (Martin Near, Sumner Thompson, Jason McStoots, and Paul Guttry alternating with Margot Rood, Owen McIntosh, Stefan Reed, and David McFerrin) on mi, then re, then ut. The Gloria followed on ut, then the Credo on mi. The choice of mode affected not only the fine tuning of harmonic intervals between the voices but also the adjustment of individual melodic lines at cadences. What we heard was beautiful articulation of the lengthy Latin texts (using French pronunciation of “-u” sounds) and extraordinary shaping of constantly interweaving melodic lines, setting Ockeghem’s intricate counterpoint in a fresh light.

The four secular songs heard after intermission displayed another facet of 15th-century polyphony, the setting of French poetry depicting the varied fortunes of courtly love. Ockeghem’s “Se vostre cuer eslongne moy a tort” (If your heart wrongfully departs from me) sets the cantus, sung by Martin Near, against a tenor (Sumner Thompson), and a supporting contratenor part played by Scott Metcalfe on a 15th-century style harp. Each line of this rondeau cinquain (rondeau with a five-line refrain) opened with primarily syllabic declamation, contrasting with an ornamental and more rhythmically flexible cadential passage. The rondeau, one of the “fixed forms” of medieval poetry, calls for initial and final recitation of the entire refrain with its music. In between, stanzas matching the first part of the refrain and its “open” musical conclusion are heard three times before a stanza matching the second part is heard, leaving the listener in a state of suspended expectation. In this case, texts for the two missing interior stanzas were provided by composer and musicologist Fabrice Fitch. Near’s rendering of the melody and its text was full of elegant nuance, with Thompson providing a well-tuned accompaniment and Metcalfe’s plucked harp contributing welcome rhythmic articulation.

We heard two anonymous pieces known only from a recently discovered songbook (known as the Leuven Chansonnier), copied probably in the Loire Valley in the 1470s and now owned by the Alamire Foundation at Leuven, Belgium. “Escu d’ennuy, semé de plours” (Shield of affliction, strewn with tears) is notable for its use of heraldic terms. The dark colors of the low-pitched setting, performed by Owen McIntosh, tenor, and David McFerrin and Paul Guttry, basses, mirrored the lover’s despair. The more light-hearted “Donnez l’aumosne, chiere dame” (Give alms, dear lady) likened the lover’s heart to a pilgrim begging for alms while on the road to Compostela. (A couplet missing from the bergerette text was supplied by Fabrice Fitch.) The performance by Margot Rood, Owen McIntosh, Jason McStoots, and Paul Guttry took care to articulate a tongue-in-cheek reading of the text.

In S’elle m’amera (If she will love me), Ockeghem applied his contrapuntal skills to a playful tour de force, combining the setting of a 21-line rondeau cinquain text in the top part (Martin Near), with that of an 8-line popular song, Petite camusette (Little snub-nose) in the lower voices (Owen McIntosh, Stefan Reed, and David McFerrin, with Scott Metcalfe adding reinforcement on the harp). The characteristic falling fifth motive that opens the song is heard in all three of the slower-moving lower parts, but also sounds at the beginning of the top part, and motives from the song permeate the melody of the rondeau throughout. This beautiful chanson with its lyrical melody could be relished as inspired interplay between learned and popular registers, based on the time-honored tradition of the borrowed cantus firmus.

Returning to the Missa cuiusvis toni, we heard the Sanctus on mi, with a sinuous tenor-bass duet in the Benedictus interlude, followed by a full-voiced Osanna. The first two invocations of the Agnus dei were also sung on mi, returning to ut for the third invocation with its quietly consoling “Dona nobis pacem” (Grant us peace). As an encore, the eight singers gave us Ockeghem’s Ave Maria for four voices ending, appropriately enough, with a Phrygian cadence on mi. To quote Guillaume Crétin’s lament on the composer’s death, this was music of an “elevated style, in which no imperfection is found.” The 19^th-century Austrian scholar August Wilhelm Ambros wrote of “the singing soul” as more essential to Ockeghem’s art than contrapuntal artifice. In their rendition of Ockeghem’s polyphony in all its complexity, Scott Metcalfe and the Blue Heron singers seem to have kept both remarks in mind, skillfully executing its virtuosic counterpoint in interweaving lines of the utmost refinement.

Virginia Newes, who lives in Cambridge, was Associate Professor of Music History and Musicology at the Eastman School of Music.