It would be hard to imagine a better program than the one played by the Bach Society Orchestra Sunday night. Consisting of Bach and Mozart, with excellent soloists, the concert played to a packed house; the audience was obviously prepared to enjoy itself, and it was not disappointed.

The program opened with Bach's Fourth Brandenburg Concerto, which conductor Michael Senturia kept at once precise and full-blooded, with especially rich, driving tone from the cellos. It was too bad the original idea of using recorders fell through, but no one could have wished for finer flute playing than that of Cynthia Crain and Fritz Kraber. Ruth Miller was mostly successful with the fiendishly difficult solo violin part, and the performance as a whole came within only a few slips in intonation of being masterful.

Pianist Robert Freeman has just completed a thesis on the cadenzas to the Mozart Piano Concerti; he must have been discouraged with what he found, as he wrote his own for the performance of the Concerto No. 24. They were short and well suited to the work, which he played magnificently. His touch was sparkling or tender as called for, and his interpretation showed meticulous care. The Orchestra was fine behind him, and, except for a tempo disagreement in the last movement, the rhythms were taut and exciting.

Bach's cantatas are the backbone of his work, and to my mind the finest body of music ever written. Using almost every conceivable combination of soloists, chorus, and orchestra, the cantatas are varied in instrumentation but maintain an astonishingly high quality. More than 200 survive, but they are played all too infrequently, and it was a real pleasure to hear Cantata No. 32, for soprano, bass, oboe, and strings.

The soloists were Sarah-Jane Smith, who, as well as having a lovely voice, is a fine musician, and Thomas Beveridge, who is a true bass and not a warmed-over baritone. Oboist Cynthia Deery played with a fine woody tone, but had a curious way of ending a phrase abruptly. The strings were fine, especially in the final duet, but the high point of the cantata was the accompanied recitative for the two soloists, with daring harmonies and beautiful, sweeping, melodic lines.

For Bach, the recitative was not merely an easy way to eat up text and set the key for the next aria, but an integral part of the musical fabric. The founder of the Orchestra, Michael Greenebaum, was on hand for the concert, and he must have been pleased to hear it giving fine performances of such great music.