Choirs are plentiful in Portland, and if you attend their concerts, you begin to notice that quite a few singers work with several of them. Yet each group has its repertory specialties, and for all their personnel crossover, no two of them sound alike. If you’re wondering what difference a conductor makes, listening to a handful of these choirs should provide an easy answer.

Renaissance Voices, the 21-voice a cappella choir that Harold Stover has conducted since 2001, produces a rich, silken tone, one of the most finely polished on the Portland choral scene. Its repertory is broad, despite the focus that its name suggests, yet elements of the Renaissance style – most notably a seamless flow and lush harmonies – seem to drive everything the choir sings, including 20th century works.

For its Christmas concert, at the Cathedral Church of St. Luke on Saturday evening (with a repeat on Sunday afternoon), Stover led the choir in a thoughtful and wide-ranging selection of sacred settings. The day’s snowstorm notwithstanding, a large audience turned up for the performance.

Most of the works Stover led were by relatively obscure composers; the best-known of them were Jacobus Clemens non Papa, Jan Pieterszoon Sweelinck, Gustav Holst and Hugo Distler. The program also included Christmas poems by Carl Sandburg, Heinrich Heine, Rainer Maria Rilke, Archibald MacLeish, Chris Wallace-Crabbe and Wesley McNair, read between groups of choral works by members of the choir.

But there were some real finds here. In the opening group, an early Baroque setting, Adrian Batten’s “O Sing Joyfully” put the spotlight immediately on the choir’s impressive blend, as did an exquisitely textured Ave Maria setting by the Flemish Renaissance master Clemens non Papa. Between them was “Hail, Lady, Sea-Star Bright,” a curious piece by Kathryn Rose.

Rose was born in 1980, but her work sounds almost Medieval, opening as it does with verses set in a plainchant style, and later expanding its harmony to take in antique-sounding open fourths. It is only at the end of the work, when Rose gives the choir a gently rocking figure and richer (but still constrained) harmonies, does the score betray its contemporary origins.

Later in the program, a setting of “The Angel’s Carol” by Crys Armbrust, born in 1957, dwelled similarly in an imagined antiquity, with only the barest hints of modern harmony peeking through neo-Renaissance style. And in a group in which works by Johannes Eccard, a 16th century composer who was on the cusp of the shift from the Renaissance to the Baroque style, were alternated with pieces by Distler, an early 20th century composer, a listener without a program book might not have guessed that nearly four centuries separate Eccard and Distler.

Like Armbrust, Distler occasionally wandered in the direction of more modern harmonies. But in some ways, the lively, extroverted Eccard pieces Stover chose sounded newer and fresher than Distler’s comparatively prim settings.

The program also included an inventive group in which the German chorale “Christum Wir Sollen Loben Schon” (with a text by Martin Luther) is traced, briskly, from its pre-Luther plainsong roots through late Renaissance versions by Lukas Osiander and Bartholomeus Gesius. Other highlights were Girolamo Baglioni’s cheerful “Factus Est Cum Angelo,” Holt’s lovely, rich-hued “Come, Ye Lofty, Come Ye Lowly,” and Charles Wood’s version of the Latin carol “Gaudete, Quia Vobis.”

Sweelinck’s “Hodie Christus Natus Est,” a celebratory work that the choir sang with an appealing combination of exuberance and dynamic suppleness, closed the program, with a quietly beautiful rendering of “Stille Nacht” (the German version of “Silent Night”) offered as an encore.

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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