Perception of Musical Similarity Among Contemporary Thematic Materials in Two Instrumentations

Free classification was used to explore similarity relations in contemporary musical materials. Thirty-four subsections from the five themes of The Angel of Death by Roger Reynolds were composed identically for piano (Expt. 1) and chamber orchestra (Expt. 2) in terms of pitch, rhythm, and dynamics. Listeners were asked to group together those judged to be musically similar and to describe the similarities between the subsections in each group. Listeners based their classifications on surface similarities related to tempo, rhythmic and melodic texture, pitch register, melodic contour, and articulation. They were to some extent also based on similarity of the mood evoked by the excerpts. This latter factor was more prominent in the verbalizations for the orchestral version. Instrumentation, timbre, and type of timbral change (smooth, disjunctive) also affected classifications in the orchestral version. Perceptual relations among thematic materials within the piece and the interaction of form-bearing dimensions in musical similarity perception are discussed.