Английская Википедия:Contrast (music)
In music and musical form, contrast is the difference between parts or different instrument sounds. The three types of contrast are rhythmic contrast, melodic contrast, and harmonic contrast.[1] Procedures of contrast include stratification, juxtaposition, and interpolation. Procedures of connection include gradation, amalgamation, and dissolution.
Harmonic contrast means to have a change in keys or chords or even cadences.
Contrast is not only a way of adding interest, and difference in a song, but is essential to the aesthetic illusion of dramatic resolution of conflict.[2]
Contrast is a sector that provides a sub-conscious break to absorb the material from the main expository piece.
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