Choeur byzantin de Grèce

Gregorian chant is the central Western tradition of plainchant: a monophonic, unaccompanied sacred song in Latin (and occasionally Greek) used in the Roman Catholic liturgy. It employs free rhythm guided by the prosody of the text rather than by strict meter, and is sung in unison by clerics or scholas. Its melodies are organized by the system of eight church modes, with characteristic finalis (final), tenor/reciting tones, and melodic formulas. Repertoires include the Proper and Ordinary of the Mass (e.g., Introit, Gradual, Alleluia, Offertory, Communion, Kyrie, Gloria, Credo, Sanctus, Agnus Dei) and the Divine Office (e.g., Antiphons, Responsories, Hymns, Psalms). Although legend credits Pope Gregory I, modern scholarship sees Gregorian chant as a Carolingian synthesis of Old Roman and Gallican chants, standardized across Frankish realms and later the broader Latin West.

Orthodox chant is the monophonic sacred singing tradition of the Eastern Orthodox Church and its related Eastern Christian rites. Rooted in the liturgy and theology of the Byzantine world, it emphasizes the primacy of text, sung in unaccompanied human voice, to convey prayer and scripture. Musically, Orthodox chant is modal, drawing on the Octoechos (a system of eight echoi/modes) that govern melodic formulas, cadences, and melodic range. Rhythmic flow follows the accent and syntax of the liturgical text rather than fixed meter; the music breathes with speech. In Greek practice since the post‑Byzantine period, an ison (a sustained drone) supports the principal melody; in many Slavic traditions, chant proceeds in unison without drone, while Georgian practice is uniquely polyphonic. Stylistically, Orthodox chant is at once austere and ornate: syllabic psalmody and hymn tones sit alongside highly melismatic psaltic art for festal moments. It is sung a cappella by choirs or solo chanters (psaltai/cantors) in Greek, Church Slavonic, Arabic, Georgian, and numerous local languages.

Byzantine chant is the monophonic, a cappella liturgical music of the Eastern Roman (Byzantine) Church, sung primarily in Greek and organized around the octoechos (eight-mode) system. Its melodies are modal rather than harmonic, unfolding in one line supported in later practice by a sustained drone (ison). The repertory sets biblical psalms and hymnic poetry (e.g., troparia, kontakia, stichera, and canons) to melodies that follow textual accent and rhetorical pacing rather than strict meter. Notation employs neumes that encode melodic direction and ornate formulae, preserving a highly codified oral tradition. The sound is characterized by free rhythm, microtonal inflections in certain modes, and an austere, prayerful timbre designed for resonant ecclesiastical spaces. Byzantine chant remains central to the worship of the Eastern Orthodox Church and has shaped a wide family of chant traditions across the Mediterranean and Slavic worlds.