This is a preliminary study of how what we call pitch was conceptualised in the fourteenth to sixteenth centuries. Its central concern is with vocally conceived, contrapuntally based polyphony around 1500, and our notational access to it. It does not deal directly with monophony (which only rarely compels a distinction between relative and fixed sounds) or with instrumental music and tablatures (which, for practical reasons, had to work with a preselected repertory of sounds). It attempts to combine some realities of performance with the testimony of contemporary theorists.