In
music, a pentatonic scale
is a
scale with five
notes per
octave. Pentatonic scales are
very common, and found all over the world: in the tuning of the
Ethiopian
krar and the Indonesian
gamelan, in the melodies of
African-American
spirituals and of French composer
Claude Debussy.
One of the most common pentatonic scales,
sometimes called a major pentatonic scale, can be
constructed in many ways. A simple 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:

Another construction, derived from
Western European classical music,
begins with a
major scale and omits the fourth
and the seventh
scale degrees: a C major scale is
{C, D, E, F, G, A, B}, so omitting the F and B again results in
the sequence {C, D, E, G, A}. The major pentatonic scale can also
be seen as all the pitches that are not present in the
major scale: in C major, the remaining pitches are G flat, A flat,
B flat, D flat, and E flat, the notes in the G flat major
pentatonic scale. These notes are also the black keys on the
piano keyboard.

A minor version of the pentatonic scale
is obtained by using the same notes as in the major pentatonic
scale, but starting one step lower to obtain the
tonic note; an A minor pentatonic
scale is A, C, D, E, G:

Only certain divisions of the octave, 12 and 20
included, allow uniqueness, coherence, and transpositional
simplicity, and that only the diatonic and pentatonic subsets of
the 12 tone chromatic set follow these constraints (Balzano, 1980,
1982). The major and minor pentatonic scales possess
Myhill's property.
The pentatonic blues scale is the minor
pentatonic with a lowered fifth:

Tuning
Deriving the pitches in a pentatonic scale from
stacked fifths leads to a Pythagorean scale of {1/1, 9/8, 81/64,
3/2, 27/16}. Deriving the pitches from the major scale leads to a
just scale of either {1/1, 9/8, 5/4, 3/2, 5/3} (a
5-limit pentatonic) or {1/1, 9/8,
21/16, 3/2, 7/4} with
blue notes of the flatted fourth
and flatted seventh.
Further pentatonic musical traditions
The pentatonic scale is very common in
Scottish music. Some scholars
believe that English
folk music was likewise at one
time a pentatonic tradition; for the reasoning behind this claim,
see
Folk music.
The major pentatonic scale is the basic scale of
the
music of China; the minor
pentatonic is used in Appalachian folk music. Both the major and
the minor pentatonic scale are commonly used
scales in jazz.
The pentatonic scales used in
Indonesian
gamelan music are called
slendro and
pelog.
Composers of Western
classical music have occasionally
used the pentatonic scale for special effects.
Maurice Ravel used it as a
pastiche of Chinese music in "Laideronette,
Empathies des Pagodes", a movement from his "Ma
Mère l'Oye" (Mother Goose) suite for
orchestra.
Frédéric Chopin wrote the right
hand piano part of his
Etude Op. 10 no. 5 in the major G
flat pentatonic scale--hence, using only the black keys.
Blackfoot music
is most often pentatonic or
hexatonic.
Hemitonic or anhemitonic
Pentatonic scales may be described as
hemitonic or
anhemitonic. Hemitonic scales
contain one or more
semitones and anhemitonic scales
do not contain semitones.
Further reading
- Tran van Khe (1977). "Le pentatonique est-il
universel? Quelques rEflexions sur le pentatonisme", The
World of Music 19, nos. 1-2:85-91. English translation
p.76-84
- Kurt Reinhard, On the problem of
pre-pentatonic scales: particularly the third-second nucleus,
Journal of the International Folk Music Council 10, 1958