Most music of Western origin is based on the concept of a tonal center. Scales, chords, and melodies all revolve around, and respond to an internal hierarchy that dictates how they sound relative to one another. The tonal center acts as the main anchor point, or home base. The tonal center, also called the key of the music, is the sounding point that the listener interprets as being totally at rest: The ear hears this as the final destination of the musical phrase or chord progression. To demonstrate this, simply play the C major scale, but stop on the note B without completing the octave. Your ear will want you to play the final C, and you will feel very uncomfortable leaving the scale unresolved. That is because in this case C is acting as the tonal center, and you are not at rest until you return there.
Music from non-Western cultures does not always contain a tonal center, which is one of the reasons some foreign music will sound so strange to Western listeners. Some twentieth century composers also experimented with twelve-tone music or atonal music, intentionally trying to eliminate the inherent musical hierarchy in Western tonal music.
A tonal center is usually established at the very beginning of the music, often by the first few notes. Tonal centers exist in all of the major and minor keys, and function in the same way: to provide the resting anchor point for the music. The sound of major key tonal centers is often associated with emotional attributes like happiness, joy, beauty, and fun. Minor key tonal centers are considered sad, moody, mysterious, and dramatic. This assignment of feelings to music is a psychological response to the establishment of the tonal center and the resulting hierarchy of the other chords and notes.
FIGURE 16-1: Major and minor tonal centers