Difficult season ends on the right note

John Harbison took to the podium as Emmanuel Music closed its season with Bach's Mass in B Minor. (Dina Rudick/Globe Staff)

Emmanuel Music's concert season came to a close on Saturday night with Bach's Mass in B Minor. John Harbison, the group's acting artistic director, was on the podium in place of Emmanuel's late founder, Craig Smith. Somehow it seemed fitting that a season that has tested the group's collective faith so intensely ended with Bach's most sweeping musical and devotional statement.

If this performance didn't have the monumentality most readings impart to the piece, it had something rarer: a feeling of naturalness and ease, an uncanny sense that at each turn, things fell exactly as they should. Harbison and Emmanuel's wonderful musicians seemed to step back and let Bach's amazing score speak for itself. The performance combined elements from both period and modern performance traditions, leading to a concert that had the lightness of the former and the deep-seated conviction of the latter.

Harbison used an unusual seating for the orchestra, putting the strings on his left and winds on his right. Having the winds so close to the front gave their sound some welcome prominence. The textures were surprisingly light, almost airy, and it's difficult to imagine densely contrapuntal movements like the two Kyries sounding clearer or more exact. The solo movements danced effortlessly. Almost all the tempos were perfectly judged, not only for the sake of musical clarity but for the spiritual message of each text. Even when the music flew - as in the joyous "Cum Sancto Spiritu" - there was an enduring sense of control and order.

The chorus sang with breathtaking skill and precision. In the Emmanuel tradition, vocal soloists were drawn from its ranks, and they were well selected. Among the standouts were soprano Kendra Colton, whose voice had appealing hints of darkness in "Laudamus te" and baritone Donald Wilkinson, who gave a potent rendition of "Et in Spiritum." Soprano Jayne West and tenor Frank Kelley looked (and sounded) as though they were having the time of their lives during the "Domine Deus" duet. The most compelling was mezzo-soprano Pamela Dellal, who gave the wrenching "Agnus Dei" a chilling sense of loneliness and abandonment.

There was a long ovation after the last washes of sound from the closing "Dona nobis pacem" had echoed away. The musicians joined the audience in heartfelt applause for Harbison, who has been crucial in guiding the group through its difficult season. True to his nature, and to Emmanuel's spirit, he acknowledged it modestly, preferring that the appreciation focus on the group as a whole.