The influence of height and key on the perceptual similarity of transposed melodies

In two experiments, the perceptual similarity between a strong tonal melody and various transpositions was investigated using a paradigm in which listeners compared the perceptual similarity of a melody and its transposition with that of the same melody and another transposition. The paradigm has the advantage that it provides a direct judgment regarding the similarity of transposed melodies. The experimental results indicate that the perceptual similarity of a strong tonal melody and its transposition is mainly determined by two factors: (1) the distance on the height dimension between the original melody and its transposition (pitch distance), and (2) the distance between keys as inferred from the circle of fifths (key distance). The major part of the variance is explained by the factor pitch distance, whereas key distance explains only a small part.