ChoralArt runs three choirs, ranging in size from 15 to 100 singers – a useful arrangement that opens the full range of repertory to the group, and at the same time, allows singers with different levels of experience and vocal polish to participate. The ChoralArt Camerata, the organization’s 15-voice chamber choir, is its elite group, an assembly of singers who can hold their own as soloists, and often do, not only in the various ChoralArt groups, but in several other Portland choirs as well.

This chamber choir, conducted by Robert Russell, was at its best on Sunday afternoon at Williston-Immanuel United Church, when it performed SpringSong, the final ChoralArt concert of the season, a program in which the first half was devoted to Mozart’s Vesperae Solennes de Confessore (K. 339), with 20th and 21st century works after the intermission.

Mozart composed his second set of Vespers in 1780 for the Salzburg Cathedral, and though the work is well down the list of his most frequently performed music, whenever it turns up, you wonder why you encounter it so rarely. Its opening Dixit Dominus and Confitebor, and the closing Magnificat are painted in bold, dramatic strokes, and if they are masterpieces of what was then the current style, the Laudate Pueri offers a vivid glance backward to the rigors of Baroque counterpoint.

The Camerata gave it a powerful, passionate reading, with most of its singers taking on solo or small ensemble lines, to superb effect. Particularly striking was Sarah Bailey’s fresh-voiced rendering of Laudate Dominum, the work’s gracefully flowing solo soprano movement. And while it’s true that Mozart’s spare but characteristically vivid orchestral accompaniment loses something in a piano reduction, Amanda Raymond, a student at the University of Southern Maine, gave it a focused, lively reading.

Russell and his singers opened the second half with sumptuous renderings of the Swedish composer and organist Waldemar Åhlén’s “Sommerpsalm,” a prayer of thanks for Sweden’s short but verdant summer, and Gabriel Jackson’s “To Morning,” an undulating, texturally rich William Blake setting.

David Conte’s “O Sun,” was composed as a memorial to the victims of the Sept. 11, 2001 attacks. Conte’s shimmering, light dissonances, and the rich counterpoint of his bass and soprano lines in the second of its two sections, illuminate a poem by John Stirling Walker that is more about calm acceptance than anger.

Conte was a student of Nadia Boulanger, as was Daniel Pinkham, whose “Alleluia for the Waters” – a work that touches on several Biblical incidents involving water – was the highlight of the program’s second half. Between those works, Russell led “Hymn au Soleil” by Lili Boulanger, their mutual teacher’s sister.

The Boulanger was the most harmonically adventurous work on the program up to that point, but the Pinkham bounded past it, taking a stylistically unsettled approach in which he glided easily between contemporary chromaticism, open harmonies in a Renaissance style, and various gradations of modernism along the way, ending with a turbulent Alleluia that leaves the Biblical allusions aside and celebrates the sheer power of water.

Here, and in Eric Whitacre’s colorful “Leonardo Dreams of His Flying Machine,” the choir sounded far bigger than a 15-voice chamber group, an effect it achieved with no sign of strain. The group closed its concert with Stephen Paulus’ “The Road Home,” a rich, beautifully harmonized setting of a melody from an 1835 songbook, with a new text by Michael Dennis Browne. Russell’s idea of having the choir sing this last piece from the side aisles – with Andrea Graichen giving a lovely account of its soprano solo, from the front of the church – proved an effective way to close this varied program.

Correction: This story was updated at 3:39 p.m. on May 11, 2017 to correct the name of the soprano who sang the solo in ‘The Road Home.’

Allan Kozinn is a former music critic and culture writer for The New York Times who lives in Portland. He can be contacted at:

allankozinn@gmail.com

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