Materials of Music - Repetition

An ability to recognize something repeated in music is very basic. This ability has many layers. Most simply something repeated over and over, a drum beat, a melodic figure, is universal to all music. A figure that repeats over and over especially as a bass line is an ostinato. These appear in popular music quite frequently and are easier to produce now because of the technology of samplers and synthesizers. Usually a inventive melodic line begins over this repeated bass which is called a "Free Part". A good deal of rap and some jazz use this formula.

Repetition, where the melodic line is longer, has a changing structure and modulation harmonically is the basic for most of the small and then the larger forms based on them.

In another dimension memory of pitch and key ( tonality) suggested by pitch comes into play.