WHAT IS BYZANTINE MUSIC?
Byzantine music is the ecclesiastical music of mainly the Greek-speaking part of the Eastern Orthodox Church. It is always performed a cappella. It is the natural evolution of the ancient Greek musical tradition, which used the modal system of scales. The modes, eight in total (four authentic and four plagal), are based upon the ancient Greek modes. The Oktoechos (eight mode system) includes modes, each with a different base (tonic) and sequence of intervals. Byzantine music uses natural untempered tetrachords and pentachords that correspond to three musical genres, the Diatonic, the Chromatic, and the Enharmonic.
As a music language it uses its own notation. This notation system, known as Parasemantike, was originally devised during the tenth century AD as a mnemonic aid to the oral tradition. In 1814, the old notation was revised and replaced by the fully prescriptive New Method of Analytical Notation.
The main difference between Parasemantike and Western staff notation is that while the latter indicates absolute the absolute pitch of each note on the staff, Parasemantike indicates the interval and quality of execution of a note in relation to the immediately preceding note. Finally, the intervals between notes are determined by the genre and mode to which a composition belongs.