Perception of Timbral Analogies
Résumé
Recent studies have investigated the structure of perceptual relations among musical instrument
timbres by multidimensional scaling (MDS) techniques. These studies have employed both
acoustically produced tones and digitally synthesized imitations and hybrids of acoustic instrument
tones. The analyses of dissimilarity ratings for all pairs of a set of tones are usually represented as
geometrical structures in a two- or three-dimensional Euclidean space in which the shared
"perceptual" axes are shown to have a qualitative correspondence to acoustic properties such as
spectral energy distribution, onset characteristics and degree of change in spectral distribution over
the duration of the tone. The present study took as a point of departure a MDS analysis for complex,
synthetic tones with the aim of testing whether musician and nonmusician listeners used the
relations defined by the perceptual space to perform an analogies task of the sort: timbre A is to
timbre B as timbre C is to which of two possible timbres, D or D'? A parallelogram model was used
to select the D timbres: if the relation between A and B is represented as a vector with both
magnitude and direction components, then the appropriate D should form a vector with C having
similar magnitude and direction in the timbre space. Aside from conceptual difficulties with the task
for both nonmusicians and composers, choices for both groups provide support for the
parallelogram model indicating a capacity in listeners to perceive abstract relations among the
timbres of complex sounds without specific training in such a task.