The
counterpart of concentus. In the ancient Church music all that
portion of the liturgical song which was performed by the entire
choir, or by sections of it, say two or three singers, was called
concentus. Thus hymns, psalms, and alleluias were, generally
speaking, included under the term concentus. On the other hand. such
parts of the liturgy as the priest, or the deacon, or subdeacon, or
the acolyte sang alone were called accentus; such were the Collects,
the Epistle and Gospel, the Preface, in short anything which was
recited chiefly on one tone, rather than sung, by the priest or one
of his assistants. The accentus should never be accompanied by
harmonies, whether of voices or of instruments, although the
concentus may receive an accompaniment. The words Gloria in excelsis
Deo and Credo in Unum Deum, being assigned to the celebrant, should
not be repeated by the choir or accompanied by the organ or other
musical instrument.
J.A. VÖLKER