Note 173 — REGISTRATION AND ORNAMENTS OF BACH’S ORGAN WORKS

B.-G. iv. [The first and last numbers, respectively, of Part I. In the first the chorale is sung by a special chorus of sopranos, usually boys, while the two mixed choruses and the two orchestras are treated contrapuntally. In the other instance the two choruses are united in one, as are also the two orchestras, and the chorale is sung by all the sopranos, the counterpoint being assigned to the remaining three vocal parts, supported by the orchestra.—Tr.]