Many of the feelings and emotions that music can evoke are a result of the tension between the consonant (pleasant) sound of some intervals, and the dissonant sound of others. During the development of western music, certain rules were established for proper harmony, and these rules specified how intervals ([[chords]]) could change over time in the music. | Many of the feelings and emotions that music can evoke are a result of the tension between the consonant (pleasant) sound of some intervals, and the dissonant sound of others. During the development of western music, certain rules were established for proper harmony, and these rules specified how intervals ([[chords]]) could change over time in the music. |