Giovanni Gabrieli

The popular historical imagination has long nourished a fascination with the cori spezzati (split choir) traditions of Venice's San Marco Cathedral. Well-known complexities of this church's architecture provide numerous locations for the placement of musical ensembles: multiple choir lofts around the altar, elevated galleries, and even oversized, raised pulpits. Though more sober historical analysis has tempered earlier concepts of a nearly Berliozian disposition of performing forces in San Marco, several generations of Venetian musicians cultivated music that exploits the contrasts between antiphonal groups. The trend culminates in the splendid polychoral motets of Andrea and Giovanni Gabrieli. Giovanni published a large collection of music by his uncle Andrea in 1587 under the title Concerti di Andrea, et di Giovanni Gabrieli, organisti della Serenissima Signori di Venetia. The published collection also contained a number of the young Gabrieli's polychoral motets for the greater liturgical occasions of the Venetian calendar. Two of his own contributions to the volume served the high feast of Christmas, the 12-voiced Angelus ad pastores, and a setting for eight voices of O magnum mysterium.

Gabrieli's O magnum mysterium consistently and classically counterpoises two contrasting vocal choirs while maintaining its elegant proportions. Gabrieli divides his text, which celebrates the lowliness of Christ's birth on Christmas, into three unequal parts; each receives a musical section of roughly equal length. The opening phrase, "O great mystery," is sung three times: once by the first choir, once by the slightly lower second choir, and a third time in climactic full polyphony. The second phrase of text, which explains that the great mystery and "wondrous sacrament" allowed mere animals to see the birth of the Savior, takes the same tripartite structure, with a temporal broadening into triple rhythmic groups. The composer packs the most text into the third section, which extols the manger and the blessed Virgin; twice Gabrieli cycles the contrasted vocal choirs, once aspirantly starting with the lower ensemble and rising to the heights. The choral antiphony becomes thus not only a vehicle for grand effect, but also serves to articulate the very structure of the text and to embody its sense. The radiant conclusion of his motet comes in a fourth section, an extended jubilant "alleluia." A series of syncopated, triple-meter antiphonal statements gradually gives way to a broad, eight-voiced tutti. Whether the two choirs braved the logistical challenges of physical separation or merely sang in proximate alternation, the effect added great luster to the Venetian liturgy.