Trinity Wall Street's Twelfth Night Festival Has Begun The early-music scene in New York is decades old, yet is still growing. The network of performers and ensembles has become broader and tighter in recent years, fed by a steady influx of young artists trained in historical-performance programs at the Juilliard School, Yale University, Queens College, New York University and elsewhere. Twelfth Night Festival Julian Wachner leading the Choir of Trinity Wall Street at Trinity Church on Saturday. At the center of the city's early-music activities is Trinity Wall Street and its intelligent, inspiring director of music and the arts, Julian Wachner, who on Saturday evening led "Noël et la Vierge Marie: a Franco-Flemish Christmas Celebration," part of the church's Twelfth Night Festival, which began on Thursday and continues through Jan. 6. The festival, in its third year, offers an enviable variety of repertory, from proto-opera (Gotham Early Music Scene's noted version of the medieval "Play of Daniel") to Baroque opera (Gotham Chamber Opera's new production of Charpentier's "La Descente d'Orphée aux Enfers," opening on Wednesday), from Italian instrumental works to late-Romantic Russian choral music. Twelfth Night may be most notable this year for including the final programs in Trinity's extraordinary celebration of Benjamin Britten's centennial. In concerts that began in September and culminate in a gala performance on Sunday, Mr. Wachner and his forces have done more than any other institution in the city to illuminate the scope and depth of Britten's achievement. One of the most valuable aspects of Trinity's centennial observance has been its ability to contextualize Britten within the tradition of religious music from which he emerged, as in Saturday's exploration of 15th- and 16th-century musical devotion to the Virgin Mary. Four of the five sections of Josquin des Prez's great "Missa de Beata Virgine" were performed alongside works by some predecessors (Gilles Binchois, Guillaume Dufay and Johannes Ockeghem), contemporaries (Jacob Obrecht and Antoine Busnois) and followers (Nicolas Gombert). All these works benefited from the shining, consonant-snapping Choir of Trinity Wall Street and from Mr. Wachner's avoidance of a too-stolid beat, which kept the music seething and propulsive even as its architecture was clearly revealed. Only in Busnois's "Gaude Coelestis Domina," with its treacherously shifting meter, did the ensemble seem at all uncertain. The ambition and creativity of the program - the choir moved to different locations in the church for different works, giving the concert the feel of a sound art installation - was impressive throughout, as was the instrumental accompaniment: the buzzy richness of the dulcian and the mellow, burnished bronze of the sackbut. The selections from Josquin's mass - especially a creamy "Kyrie," blossoming "Credo" and grandly lilting "Sanctus" - were the featured attraction, but the highlights for me were two works by Gombert: a dense setting of "Salve Regina," which unfolded with the deliberate yet surprising logic of a mathematical proof, and an astonishing 12-voice "Regina Coeli." The Twelfth Night Festival continues through Jan. 6 at various locations; trinitywallstreet.org/twelfthnight.