Human listener's judgment of musical timbre similarity.

<p>(<b>A</b>) The mean (top row) and standard deviation (bottom row) of the listeners' responses show the similarity between every pair of instruments for three notes A3, D4 and G#4. Red (values close to 1) indicates high dissimilarity and blue (values close to 0) indicates similarity. (<b>B</b>) Timbre similarity is averaged across subjects, musical notes and upper and lower half-matrices, and used for validation of the physiological and computational model. (<b>C</b>) Multidimensional scaling (MDS) applied to the human similarity matrix projected over 2 dimensions (shown to correlate with attack time and spectral centroid).