Timbre, in contrast to the other fundamental elements of sound, is defined by what it is not. It is not the pitch, loudness, intensity, or duration of sound. It is everything else. Timbre is the color of sound. Every instrument, for example, has its own shade, its own nuances. Obviously, the colors are not visual. A clarinet does not sound green or purple, but a clarinet does have a unique auditory texture or color that psychoacousticians, scientists who study sound perception, call timbre.
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