‘THESE ARE THE TONES COMMONLY USED’: THE TONOS DE CANTO DE ÓRGANO IN SPANISH BAROQUE MUSIC THEORY.

In the course of the seventeenth and eighteenth centuries, composers and music theorists moved away from the system of the eight ecclesiastical modes that had been elaborated by medieval theorists and was later applied to polyphonic music (including the varied system extended to twelve modes in the sixteenth century) towards modern bimodal tonality. Although several modal systems coexisted within this time period, a distinct variant of the eight modes, often known in modern scholarship as the church keys, developed as a practical solution to problems associated with the performance of psalms and other recited formulas (especially the Magnificat) in alternatim practice between the choir in plainchant and the organ. A scarcity of research on this topic within investigations of Spanish music prompts us to outline an introduction to a matter so crucial to music theory of the baroque period in Spain. Thus we present an overview of the treatment of the church keys or tones in Spanish treatises over a long period of two centuries, and focus briefly on particular contributions made by individual authors. [ABSTRACT FROM AUTHOR]