Choralis
Gregorian-style setting in the manner of chant.
What it means
Choralis is the Latin adjectival form of chorale (chant) and appears above all in book titles and work designations of the Renaissance and Baroque, for instance when a collection designates chants after the chant model or contains settings over chant melodies. What is meant is a relation to monophonic liturgical singing: either it is the chant itself, a polyphonic setting over a chant melody, or a piece modelled on the style of chant.
Musical use
Drawing on chant melodies is one of the most important compositional techniques of older European music. A given melody is placed as a cantus firmus in one voice, usually in long note values, while the other voices play around it. In this way a connection arises between the liturgical tradition and artful polyphony. In the Protestant sphere too the principle lives on, there with the melodies of the church hymn, which are worked out in the chorale prelude, the chorale setting, and the cantata. The designations in the sources are not uniform and must be checked in each case.
Performance practice
With a setting over a chant melody, first determine in which voice the given melody lies, and make it audible without suppressing the other voices — especially in long note values it would otherwise be lost. Know the underlying melody and its text, because articulation and emphasis follow from it. With organ settings choose a registration that sets off the cantus firmus, for instance by a solo stop on a manual of its own. Check the origin of the version of the melody used, since chorales are transmitted in different variants.
Bear in mind that chorale melodies circulated in different rhythmic versions: the same melody can be transmitted in even or in unequal values, and composers presuppose now one, now the other shape. Check therefore which version a setting uses, and adapt the congregational accompaniment to it where necessary. With organ settings it is worth knowing the text of the corresponding stanza, because it guides registration and articulation. Keep the melody audible even in dense figuration around it.