---
title: "Hagiopolitan Octoechos"
chunk: 4/11
source: "https://en.wikipedia.org/wiki/Hagiopolitan_Octoechos"
category: "reference"
tags: "science, encyclopedia"
date_saved: "2026-05-05T03:39:20.479308+00:00"
instance: "kb-cron"
---

According to the Latin synthesis the plagal and authentic tones of protus, deuterus, tritus, and tetrardus did not use the same ambitus as in the Hagiopolitan octoechos, but authentic and plagal tones used both the finalis of the plagios, so that the finalis of the kyrios, the fifth degree of the mode, was no longer used as finalis, but as repercussa: the recitation tone of the authentic tone used in a simple form of psalmody which was another genuine invention by the Carolingian reformers. The ambitus of the authentic tones was made up the same way as used in the Greek octoechos, while the plagal tones used a lower ambitus: not the tetrachord above the pentachord, but below it. Hence, the hypodorian octave referred the tonus secundus and was constructed A—D—a, and the dorian as "tonus primus" D—a—d, both tones of the protus used D as finalis, the hypophrygian octave species was B—E—b and was the ambitus of the tonus quartus, and the phrygian octave species E—b—e was related to the tonus tertius and its finalis E belonged to the deuterus, the hypolydian octave species C—F—c was connected with the tonus sixtus, the lydian octave F—c—f with the tonus quintus and both shared the finalis F called tritus, the last was the seventh octave species G—d—g called "mixolydian" which referred to the tonus septimus and its finalis G.

=== Tonary ===