ABSTRACT
Medieval liturgy is reliant on interdependence between those in choir and presbytery in a cathedral, or chancel and sanctuary in a parish church. In a number of instances clergy, servers and singers could draw on their experience of these roles in modern liturgy; and experience in one modern role could be transferred to a different medieval one. The compact nature of the chancel of St Teilo's Church generated both intimacy and intensity at the Lady Mass. Priest, deacon, subdeacon, servers and singers were physically separated from the rest of the church in an enclosure, bounded on three sides by wooden screens. The use of the organ in alternation with the singers for Kyrie, Sanctus and Agnus Dei in the Jesus Mass, placed sonic emphasis on the Ordinary of the Mass through polyphonic embellishment typical of the sixteenth century. It also offered the opportunity for both organist and singers to investigate the practice of polyphonic improvisation on a chant.
