It has become easy to win over new students to the study of fifteenth-century music. The widespread availability of recordings of Du Fay, Josquin, and others puts the sonorous qualities of this music on full display. This chapter begins with the autobiography of Johannes von Soest, one of the most loquacious witnesses to the listening experiences of fifteenth-century art music. It provides an encapsulation of the essential modes of perception of late medieval art music. The chapter focuses on the doctrine of the internal senses and their effect on music comprehension with a special focus on the spiritual efficacy of sacred polyphony and the considerable critique that this music engendered. The doctrine of the spiritual senses made possible an unmediated affective access to God, distinct from representations of the angels in their multitude of merely intellectually perceptible music. Finally, the chapter discusses the justification of earthly sensual pleasure, including the "listening pleasure" of sacred music.