Despite its number of informal madrigal groups, the University has rarely boasted a permanent ensemble devoted to chamber-size choral music. But from casual origins several years ago, the Bach Society Chorus of the Music Club has gradually come to fill this gap.

The motet Jesu, Meine Freude, which opened the Society's Sunday concert, exemplifies one difficulty peculiar to music for "chamber chorus." In a small group, Bach's vocal demands--no matter how great--cannot be conveniently ignored by concentrating purely on massed sound. When the Bach Society Chorus disappointed at all, it did so in technical respects. Conductor Howard Brown clearly brought out individual lines of counterpoint, but the sheer effort required to sing all the notes reasonably in tune resulted in a tone that was often coarse and piercing.

Five Landscapes, by assistant professor of Music Allen Sapp, made fewer requirements of range, and the chorus responded with far more attention to details of tonal quality. Mr. Sapp is blessed with a poetic sense to match his extraordinary musical gifts. Taking five poems of T. S. Eliot, he has not merely assigned each syllable a note and made the work a straight declamation. Rather, he has readily displaced certain lines to enhance the lyrical effect.

Glance aside, not for lance, do not spell

Old enchantments . . . . .

Lower voices repeatedly chant "glance aside," while the sopranos sing in a more sustained line of "old enchantments." And the evocation of magic "where the greylight meets the green air" ends with the climactic cry "Suddenly!"--a word lifted from the poem's opening line.

Inclusion of a solo cantata in Sunday's program provided excellent contrast to the choral sound. Above all, Rameau's Le Berger Fidele requires style to sustain the text's nonsense. Fortunately the soloist was Jean Lunn, whose lovely voice is not yet tired from a heavy concert schedule. Her phrasing, diction, and impeccable vocal ornamentation placed the cantata's fluffiness in a proper musical perspective.