Complex sentence: He wrote comic operas and incidental music for plays, but was most widely known for his choral music--he also achieved distinction as a director of choral groups, teacher of voice and a member of choral competition juries.
Split into simpler sentences: He wrote comic operas and incidental music for plays, but was most widely known for his choral music. He achieved distinction as a director of choral groups, teacher of voice and a member of choral competition juries.