Perceptual Judgments of Triads and Dyads: Assessment of a Psychoacoustic Model

In two experiments, goodness-of-fit ratings of pairs of musical elements (triads, dyads, and octave-complex tones) were examined in view of a psychoacoustic model. The model, referred to as the pitch commonality model, evaluates the sharing of fundamental frequencies, overtones, and subharmonic tone sensations between sequential elements and also considers the effects of auditory masking within each element. Two other models were also assessed: a reduced model that considers the sharing of fundamental frequencies alone and the cycle-of-fifths model of key and chord relatedness. In Experiment 1, listeners rated the goodness of fit of 12 octave-complex tones following a major triad, major-third dyad, and perfect-fifth dyad. Multiple regression revealed that pitch commonality provided predictive power beyond that of the reduced model. A regression model based on pitch commonality and the cycle of fifths had a multiple R of .92. In Experiment 2, listeners rated how well a triad or dyad followed another triad or dyad. All pairings of the major triad, major-third dyad, and perfect-fifth dyad (pair types) were presented at various transpositions with respect to one another. Multiple regression revealed that pitch commonality again provided predictive power beyond that of the reduced model. A regression model based on pitch commonality, the cycle of fifths, and a preference for trials ending with a triad had a multiple R of .84. We discuss the role of psychoacoustic factors and knowledge of chord and key relationships in shaping the perception of harmonic material.