Pentatonic scale

A pentatonic scale is a musical scale or mode with five notes per octave in contrast to a heptatonic (seven-note) scale such as the major scale and minor scale. Pentatonic scales are very common and are found all over the world. They are divided into those with semitones (hemitonic) and those without (anhemitonic).

Pentatonic scales occur in the following traditions:

Examples of its use include Chopin's Etude in G-flat major, op. 10, no. 5, the "Black Key" etude, in the major pentatonic.

Musicology commonly classifies pentatonic scales as either hemitonic or anhemitonic. Hemitonic scales contain one or more semitones and anhemitonic scales do not contain semitones. For example, in Japanese music the anhemitonic yo scale is contrasted with the hemitonic in scale. Hemitonic pentatonic scales are also called "ditonic scales", because the largest interval in them is the ditone (e.g., in the scale C–E–F–G–B–C, the interval found between C–E and G–B). This should not be confused with the identical term also used by musicologists to describe a scale including only two notes.

Anhemitonic pentatonic scales can be constructed in many ways. The major pentatonic scale may be thought of as a gapped or incomplete major scale. However, the pentatonic scale has a unique character and is complete in terms of tonality. One construction takes five consecutive pitches from the circle of fifths; starting on C, these are C, G, D, A, and E. Transposing the pitches to fit into one octave rearranges the pitches into the major pentatonic scale: C, D, E, G, A.

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