Timbre is the least understood of the components: calling it “tone color” is vague at best. Standard music notation doesn’t deal with it at all. Timbre arises from the fact that all sounds are not just one pitch, but a cluster of pitches. The brain sorts them out and locates a central focus for practical purposes. But the whole buzzing “envelope” of the other pitches—“overtones,” “partials,” or “ harmonics”—does color the meaning of the pitches. The response can be simply “oh, that’s a cello, not a voice” but also “that’s a woman,” or “that person is sad,” or “great guitar sound.” Timbre is basic to folk aesthetics and can even lie at the heart of the matter, as among the Tuvans of Siberia, who have what Ted Levin calls a “timbre-centered music,” with their intense concentration on the sonic splendor they can coax from their vocal resources as part of their deeply ecological imagination. Intensity has to do with what’s usually called “volume,” measured in decibels (db). Over a certain number of db, sounds gets painful, as any careless iPod user or anyone walking down a big-city street can testify. Today, unlike all of previous human history, loud and unpleasant sound is actually used as a torture device by armies, a practice that is unbelievably remote from the life of folk music. Several societies make distinctions between indoors and outdoors music based on intensity. Today, even the loudest sounds that acoustic instruments could make seem subdued in comparison to a dance club, but people lived in an entirely different acoustic world—for a million years or more—before the twentieth century. They had another frame of reference for “loud” and “soft.”