PORTLAND – The Christmas concert of the St. Mary Schola on Tuesday night at the Cathedral Church of St. Luke was, as usual, carefully programmed and angelically sung.

This year’s musical offering also included a baroque ensemble – violins, viola, recorders, cello and viol da gamba – tuned to “old pitch,” usually A-415 Hz, as compared to the A-440 Hz pitch of the modern orchestra.

The half-step down not only sounded authentic, but also enhanced the baroque works on the program, as if they were happy to be home. Cheerfulness was the mood of the evening, with not a Gregorian chant in sight.

Director Bruce Fithian has built the choir around six voices, soprano, mezzo soprano, tenor, counter-tenor, bass and baritone, an ideal configuration for both renaissance and baroque choral music. Orchestral accompaniment allows them to sing at perfect intervals, like an a cappella chorus.