Papadic Octoechos

Oktōēchos (here transcribed "Octoechos"; Greek: ὁ Ὀκτώηχος, pronounced in Constantinopolitan: Greek pronunciation: [oxˈtóixos]; from "eight" and "sound, mode" called echos; Slavonic: Осмогласие, Osmoglasie from "eight" and "voice, sound") is the name of the eight mode system used for the composition of religious chant in Byzantine, Syriac, Armenian, Georgian, Latin and Slavic churches since the Middle Ages. In a modified form the octoechos is still regarded as the foundation of the tradition of monodic Orthodox chant today.

Until 1204 neither the Hagia Sophia nor any other cathedral of the Byzantine Empire did abandon its habits, and the Hagiopolitan eight mode system came into use not earlier than in the mixed rite of Constantinople, after the patriarchate and the court had returned from their exile in Nikaia in 1261.

In the history of the Byzantine rite the Hagiopolitan reform was described as a synthesis of the cathedral rite and the monastic rite. Nevertheless, the Hagiopolitan octoechos did not come into use at the Hagia Sophia of Constantinople before the Papadic reform during the late 13th and the 14th century, after the patriarchate and the court had returned from exile in Nicaea. The reform of John Koukouzeles can be studied by a new type of treatise called "Papadike" (ἡ παπαδικὴ). It included a list of all neume signs which were taken from various chant books and their different notation systems. In the school of John Glykys this list had been organized as a didactic chant called Mega Ison which passed through all the eight echoi of the octoechos, while the singers memorize the signs and studied their effect in chant composition. This chant or exercise (μάθημα) had been invented by John Glykys, but most papadikai also add a second version in the redaction of John Koukouzeles who was probably his student. These lists prefer the use of Byzantine round notation, which had developed during the late 12th century from the late diastematic Coislin type. The modal signatures were referred to the Hagiopolitan octoechos. Because the repertoire of signs was expanded under the influence of John Glykys' school, there was a scholarly discussion to make a distinction between Middle and Late Byzantine notation. The discussion decided more or less against this distinction, because the Papadic school did not invent new neume signs, it rather integrated signs known from other chant books and their local traditions, including the books of the Constantinopolitan cathedral rite as they had been used until the Western conquest of Constantinople.

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