CHAPEL, COMPOSITION FOR
a. — During the period of the greatest splendor of polyphonic music, when the most notable centers of musical life were chapels and the most celebrated among composers were precisely singers or directors (maestros) of them, the term “composition for chapel” generically indicated all church compositions in polyphonic style, the performance of which was entrusted to choirs, not supported by any instrumental accompaniment.
The term continued to mean this even when (end of the 15th century) in some chapels the innovation was accepted of accompanying sacred offices with the sound of certain instruments, and when, in the 16th and 17th centuries, the importance of organists in chapels became of primary significance (A. and G. Gabrieli in the chapel of St. Mark in Venice). In Germany, properly choral singing, very much in vogue in the 15th–16th centuries, then diminished in importance, since there the use of instrumental timbres in religious music became highly developed, blending human voices (“solo” or “choir”) with instrumental timbres, especially in the various forms of the so-called concertato style.
One spoke of “choral time” (or “alla breve”) for that type of rhythmic division in which the measures are constituted by a breve, or four minims; it was widely used in ancient church music, when the unit of measure was the minim, which seems ordinarily to have had a duration value similar to our modern semiminim. Moderately, choral time or alla breve can mean a 2/2 time (or even an ordinary 4/4 time, beaten more quickly), marked to indicate the division of the measure into 2 minims; or it can still mean a 2/1 time, marked C or also, but more rarely, C/O (from the ancient sign C/O by which the breve sometimes assumed the value of a unit of measure, corresponding to 3 rather than to 2 semibreves).