OCCASIONALLY DURING a concert an orchestra achieves an emotional rapport with its audience which transcends the notes. Last Saturday night during its last performance of the season, the Bach Society and the Sanders Theatre audience struck a sympathetic chord as they bade farewell to this year's conductor, Neal Stulberg '76.

The evening began with a joke. Seven members of the orchestra played the Schleptet in E flat, S.O., by musicologist Peter Schickele, more familiarly known as P.D.Q. Bach (1807 -- 1742), the last and the least of Johann Sebastian's sons. Satirizing serious music, the Schleptet demands a wide range of comic effects, including a nose-dive by the French horn player, which sends fragments of a collapsible horn sailing across the stage into the audience, and woodwind burps usually reserved for a beginner's practice room.

The real program opened inauspiciously with the introduction of Mozart's Symphony No. 39 in E flat sounding tentative and timid. Perhaps Stulberg intended to set off the later robust sections of the movement with his restrained opening, but he drew a sound more anemic than richly resonant. During this section, moving lines in the lower strings were buried by enthusiastic violins. In the slower second movement, the group seemed to recover from its weak start as Stulberg set an easy pace for the almost religious lyrical passages that followed. He allowed the audience to revel in Mozart's rich, melancholy harmonies. Some well-placed accents would have given the ensuing third movement the bounce it sorely missed. Stulberg picked up the tempo for the final allegro. His careening pace in the finale left his players nearly breathless. Their fleeting runs, although technically accurate for the most part, sounded harsh and forced.

After the intermission the orchestra seemed revitalized as they accompanied Sheila Reinhold, a special student, in a stunning performance of Prokofiev's Violin Concerto No. 2. Stulberg and the Bach Society nimbly handled the complicated rhythms. Even during tutti passages the group never covered the soloist. Gliding through frequent changes in mood from sad to satirical, Reinhold maintained complete control. She demonstrated an exquisitely pure tone amidst the large intervallic leaps which Prokofiev loved to inflict on musicians.

THE MOMENTUM GAINED in the Prokofiev swept the orchestra through a rousing performance of Brahm's Variations on a Theme by Haydn--the first example in musical literature of orchestral variations written as an independent work. Stulberg ably held the work together, preventing the variations from fragmenting into eight separate pieces. By skillfully distributing the climaxes, he molded the variations into one symphonic statement. The sections of the orchestra played with a delicate balance, clearly voicing each line.

The finale of the Brahms work provided a fitting conclusion to the Bach Society's year and to Stulberg's career as its conductor. Both the orchestra and the audience responded enthusiastically to the resounding final chords of the piece, sharing the poignantly conflicting feelings associated with the end of an outstanding year. In its technical polish and emotional fervor, the performance of the Brahms was emblematic of the Bach Society's season.