Chorus; Ensemble

Vocal part music has been associated with music of the theater and the church.  In the church setting the vocal ensemble was generally referred to as a choir, while in the dramatic mediums of opera and oratorio, the large vocal ensembles were considered choruses.

The structure of a work or section for chorus has no specific formal characteristics.  In the 17th century, contrapuntal texture generally prevailed in the oratorio and mass, whereas homophonic texture frequently invaded operatic writing.  Because of the emphasis on solo singing, choral passages were infrequent in Baroque opera, and occurred only when dramatic incidents required it as part of the action.

In the 18th century, works or sections for ensemble (smaller vocal group, usually one singer per part) were written as well as music for the larger chorus.  Haydn, for example, wrote several such works.  The Moravian church, centered in Pennsylvania and North Carolina, generated a sizable repertory of music for various vocal combinations, usually with instrumental accompaniment.  The performance of the music of this tradition continues today.

The chorus is an effective part of the drama in the operas of Gluck and Mozart.  Ensembles, especially in Mozart, marvelously present subtle musical dramatization.  In contrast to the homophonic texture of arias, these choruses and ensembles are usually polyphonic.  Each member of the ensemble is often declaiming elements of counterplots and intrigue along with the main story.  In essence, this is both musical and dramatic counterpoint.