Messes de l'homme armé

Plainchant (cantus planus) is the monophonic, unaccompanied chant of the Western Christian liturgy. Sung in Latin (with occasional Greek), it uses modal scales rather than major–minor tonality and unfolds in flexible, speech-like rhythms shaped by the sacred text. Melodically, plainchant ranges from simple syllabic formulas for reciting psalms to ornate melismatic lines for processional and festal moments. It is performed in unison by a schola or congregation, often organized antiphonally or responsorially across the liturgical actions of the Mass and the Divine Office. Its austere sonority, modal color, and text-centered phrasing give it a contemplative, timeless quality.

Ambrosian chant is the liturgical plainchant of the Ambrosian Rite, practiced primarily in and around Milan, Italy. It is one of the few non-Gregorian Latin chant traditions to survive in continuous use, and is closely associated with the legacy of St. Ambrose (4th century). Like other plainchant, it is monophonic, unaccompanied, and sung in Latin, but it has its own melodic idioms, modal organization, and liturgical genres distinct from the Roman (Gregorian) tradition. Its rhythms are free and speech-like, designed to carry sacred texts clearly and reverently rather than follow metrical patterns. Ambrosian hymnody, often in iambic dimeter, is a hallmark, reflecting the formative influence of early Milanese practice and Eastern antiphonal singing.