How the rhythms, timbres, melodic, and harmonic materials are combined in a composition. They can be considered "thick" if there are many musical layers or "thin" if there are only one or two layers. *

Music incorporates all of the following factors already listed. Melodies are the principal aspect of a composition. It uses rhythm and pitches to make consonance, a pleasant timbre, or in other words to make a good sound. Generally, in music, harmony refers to chord structure, and most chord structures are based of scales and uses diatonic notes to make chord progressions that sound rather pleasant. If it doesn't use the notes within that certain scale. It would be considered atonal, or non-diatonic. The usage of atonality was most used during the 20th Century where that musical period was used for exploration and breaking the boundaries of music. In terms of "thick", it would mean there are many parts in the music, or in other words, it would be considered polyphonic, or homophonic.

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