Pentatonic scale
A pentatonic scale is a musical scale with five pitches per octave as compared to the major scale which is made up of seven distinct notes. Pentatonic scales are very common and are found all over the world, including but not limited to Celtic folk music, African-American spirituals, American Blues Music and Rock Music, children's songs, the clarinet Music of Epirus in northwest Greece and Southern Albania[1], the tuning of the Ethiopian krar and the Indonesian gamelan, the melodies of Japanese and Chinese Folk Music, Polish highlanders from the Tatra Mountains, and Western Classical composers such as French composer Claude Debussy.
Types of pentatonic scales
Hemitonic and anhemitonic
Ethnomusicology 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, a hemitonic pentatonic scale common in some areas of North and West Africa contains flatted 2nd, 3rd, and 6th degrees (hence, if the scale begins in C, it will contain a D-flat, E-flat, and A-flat, plus a G-natural).
Major pentatonic scale
Anhemitonic pentatonic scales can be constructed in many ways. 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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Another construction works backward: It omits two pitches from a diatonic scale. If we were to begin with a C major scale, for example, we might omit the fourth and the seventh scale degrees, F and B. The remaining notes, C, D, E, G, and A, are transpositionally equivalent to the black keys on a piano keyboard: G-flat, A-flat, B-flat, D-flat, and E-flat.
We can also omit the third and seventh degrees of the C major scale to obtain the notes another transpositionally equivalent anhemitonic pentatonic scale: {F,G,A,C,D}. If we omit the first and fourth degrees of the C major scale we have a third anhemitonic pentatonic scale: {G,A,B,D,E}.
Minor pentatonic scale
Although various hemitonic pentatonic scales might be called minor, the term is most commonly applied to the relative minor pentatonic derived from the major pentatonic, using scale tones 1, 3, 4, 5, and 7 of the natural minor scale. Thus C minor pentatonic would be C, E-flat, F, G, B-flat. The A minor pentatonic, the relative minor of C, would be the same tones as C major pentatonic, starting on A, giving A, C, D, E, G. This minor pentatonic contains all three tones of an A minor triad.
Songs on the minor pentatonic scale include the popular children's song "Land of the Silver Birch" often sung in day care centers. Because of their simplicity, pentatonic scales are often used to introduce children to music. Other popular children's songs are almost pentatonic. For example, the almost-pentatonic nature of the Gershwin lullaby "Summertime", is evident when it is played in the key of E-flat minor. In that key, the melody can be played almost entirely on the black keys of a piano, except just once per verse, where a white key is needed.
Tuning
If we proceed by the principle that historically gives us the Pythagorean diatonic and chromatic scales, stacking perfect fifths with 3:2 frequency proportions, we can tune an anhemitonic pentatonic scale thus: 1:9/8:81/64:3/2:27:16. If we consider the anhemitonic scale a subset of a just diatonic scale, we can tune it thus: 1:9/8:5/4:3/2:5/3. Assigning precise frequency proportions to the pentatonic scales of most cultures is problematic. The slendro anhemitonic scales of Java and Bali are said to approach, very roughly, an equally-tempered five note scale, but, in fact, their tunings vary dramatically from gamelan to gamelan. Specially trained musicians among the Gogo people of Tanzania sing the fourth through ninth (and occasionally tenth) harmonics above a fundamental, which do necessarily accurately correspond to the frequency proportions 4:5:6:7:8:9, but this is not a scale in the western sense because these pitches are not found within a single octave and could not be put into a single octave with this manner of performance. If they could be and were put into a single octave, however, they would make a pentatonic scale with these frequency proportions: 1:9/8:5/4:3/2:7/4.
Further pentatonic musical traditions
The major pentatonic scale is the basic scale of the music of China and the Music of Mongolia. The fundamental tones (without meri or kari techniques) rendered by the 5 holes of the Japanese shakuhachi flute play a minor pentatonic scale. The Yo scale used in Japanese shomyo Buddhist chants and gagaku imperial court music is a pentatonic scale, shown below.[1]
The slendro scale used in Javanese gamelan music is pentatonic, with roughly equally spaced intervals. Another scale, pelog, has seven tones, but is generally played using one of several pentatonic subsets (known as pathets), which are roughly analogous to different keys or modes.
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 minor pentatonic is used in Appalachian folk music. Blackfoot music is most often pentatonic or hexatonic.
Both the major and the minor pentatonic scales are commonly used in jazz (notably by jazz pianists Chick Corea and Herbie Hancock), blues, and rock. Pentatonic scales are useful for improvisors in modern jazz, pop, and rock contexts because they work well over several chords diatonic to the same key, often better than the parent scale. For instance, over a C major triad (C, E, G) in the key of C major, the note F can be perceived as dissonant as it is a half step above the major third (E) of the chord. It is for this reason commonly avoided. Using the major pentatonic scale is an easy way out of this problem. The scale tones 1, 2, 3, 5, 6 (from the major pentatonic) are either major triad tones (1, 3, 5) or common consonant extensions (2, 6) of major triads. For the corresponding relative minor pentatonic, scale tones 1, ♭3, 4, 5, ♭7 work the same way, either as minor triad tones (1, ♭3, 5) or as common extensions (4, ♭7), as they all avoid being a half step from a chord tone.
The pentatonic scale occurs in popular music - for example in Ol' Man River. It is also a staple ingredient of film music, where it is used as a shorthand to signal primitive or exotic contexts. With suitable changes in orchestration it can be used to depict an Oriental setting, a scene with American Indians, or a rustic hoedown.
Composers of Western classical music have occasionally used pentatonic scales for special effects. Antonín Dvořák, inspired by the native American music and African-American spirituals he heard in America, made extensive use of pentatonic themes in his "New World" Symphony and his "American" Quartet. Maurice Ravel used it as a basis for a melody in "Passacaille," the third movement of his "Trio in A Minor" for Violin, Cello and Piano, and as a pastiche of Chinese music in "Laideronette, Emperatrice des Pagodes", a movement from his Ma Mère l'Oye (Mother Goose). Frédéric Chopin wrote the right hand piano part of his Etude Op. 10 no. 5 in the major G-flat pentatonic scale, and therefore, the part is played using only the black keys. Incidentally, the common pentatonic major and minor scales (C-D-E-G-A and C-Eb-F-G-Bb, respectively) are useful in modal composing, as both scales allow a melody to be modally ambiguous between their respective major (Ionian, Lydian, Mixolydian) and minor (Aeolian, Phrygian, Dorian) modes (locrian excluded).
Use in education
The pentatonic scale plays a significant role in music education, particularly in Orff-based methodologies at the primary/elementary level. The Orff system places a heavy emphasis on developing creativity through improvisation in children, largely through use of the pentatonic scale. Orff instruments, such as xylophones, bells and other metallophones, use wooden bars which can be removed by the teacher leaving only those corresponding to the pentatonic scale, which Orff himself believed to be children's native tonality [citation needed]. Children begin improvising using only these bars, and over time, more bars are added at the teacher's discretion until the complete diatonic scale is being used. Orff believed that the use of the pentatonic scale at such a young age was appropriate to the development of each child, since the nature of the scale meant that it was impossible for the child to make any real harmonic mistakes.
Further reading
- Pentatonicism from the Eighteenth Century to Debussy by Jeremy Day-O'Connell (University of Rochester Press 2007) - the first comprehensive account of the increasing use of the pentatonic scale in 19th century Western art music, including a catalogue of over 400 musical examples.
- Tran Van Khe "Le pentatonique est-il universel? Quelques reflexions sur le pentatonisme", The World of Music 19, nos. 1-2:85-91 (1977). 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).
- Jeff Burns, Pentatonic Scales for the Jazz-Rock Keyboardist (1997).
See also
References
- http://home.earthlink.net/~llywarch/scl01.html.htm abstract of detailed examination of scale in Southern Appalachian folksong and other music of the Celtic diaspora
External links
