ABSTRACT
This chapter aims to assemble the information that actually tells them something about the performing ensembles used in polyphony. Modern writers have repeatedly affirmed that composed polyphony was only a small part of mediaeval man's musical experience. Even in the grandest cathedrals and court chapels, plainchant was sung daily whereas polyphony was for the most part confined to special occasions; and simple improvised or semi-improvised polyphony looks increasingly important in mediaeval Europe. Monophonic song remained a prominent musical embellishment to the rich courts just as it was ubiquitous in the towns. The social historian may be interested in all kinds of music making, but the student of the music that happens to survive needs to know what was thought to be the ideal performance, the one that is worth emulating in an attempt to revive the music. In most surviving music of the time the tenor and the contratenor lines occupy the same range.
