Tonar

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A tonar, also tonarium, tonarius or tonale, is the compilation of Gregorian chants ordered by tone (modes), as it became common since the early Middle Ages.

The history of the toner as a choral didactic work begins in the 9th century. century and ends in the late Middle Ages. Tonars are important tools for researching the dubious tonality of individual melodies and serve to develop a choral theory.

Significant authors are Regino von Prüm, Hartker von St. Gallen, Odo von Cluny and Berno von Reichenau.

Function and form
Tonars were especially important as part of the written transmission from the parish, although they already completely changed the oral singing transmission of the Frankish cantors before the musical notation was used systematically in fully recorded hymnbooks. Since the Carolingian reform, the new order after the octoechos supported the memorization of singing. The exact order referred to the elements of the “Tetrachord of the Final” (D–E–F–G), which were called “Protus, Deuterus, Tritus” and “Tetrardus”. Each of them served as the finalis of two Toni – the “authentic” (ascending into the higher octave) and the “plagal” (descending into the lower fourth). The eight notes were arranged in these pairs: “Autentus protus, Plagi Proti, Autentus Deuterus”, etc. Since Hucbald of Saint-Amand, the eight tones have been numbered simply by this order: Tonus I-VIII. Aquitan cantors usually used both names for each section.

The Different Forms of a Tonar
Tonars can differ significantly in length and shape:

As a treatise, they usually describe the octave, the fifth and fourth types of each tone, but also their modal properties such as microtonal shifts or the change to another melodic frame.
It can also be an abbreviated form or a breviary showing only the sacramentary (for mass singing) or antiphonary (for the official singing of the vigils and the hours) after the liturgical year. The tone of the antiphonic singing genres is indicated by later rubrics such as “ATe” for “Autentus Tetrardus” (see the Graduale Sacramentaries of Corbie and Saint-Denis) or the Roman Ordinal Numbers I-VIII according to Hucbald’s system, as can be seen in the early Troper Sequentiary of St. Géraud in Aurillac (F-Pn lat). 1084) and the abbreviated antiphonar of St. Martial (F-Pn lat. 1085) can be found.
The most common form was the shortest, which had no theoretical explanation. Since the late 9th century, each section began with an intonation formula and the psalm of fashion, whose pitches are represented by letters or later by diastematic new notation. Subsections followed the various vocal genres, which were cited as examples of the tone represented. Antiphonal refrains in the Psalm recitation (Ant)