Last night's Bach Festival concert in the Church of the Ascension and St. Agnes offered the concerto for oboe and violin and two cantatas. Louise Lee conducted the Ad Hoc Singers and a chamber orchestra in the cantatas, after serving as harpsichordist in the concerto.

Janet Piez had a busy evening, playing the oboe in the concerto as well as the demanding solos in the cantatas. Her tone was expressive and she made a fine and happy sound in the rapid pages of the famous aria, "Endlich, endlich" of Cantata No. 56, "I Will Gladly Bear the Cross." This is one of Bach's two solo cantatas for bass. Michael Donaldson was the soloist, singing musically in the long, coloratura lines.

Though he is a baritone, which placed some of the lower writing in the cantata out of his reach, he carried off the lengthy assignment creditably. tThe opening aria is one of Bach's difficult scenes, with the insistent use of his "weeping" motif, two eighth notes in descending order. At times they became a bit oppressive from both singer and instruments.

David Brewster, solo violin in the concerto, projected the music with a good sense of style. In Cantata 131, "Aus der Tiefe," David Richie's lyric tenor sounded attractive, though he, like everyone else at one time or another in the program, had minor problems in arriving precisely at the center of the notes. Tonight: the Washington Consort directed by Reilly Lewis. The concerts are free.