Altered scale
Encyclopedia
In jazz
, the altered scale or altered dominant scale is a seven-note
scale
that differs from the Locrian mode
in having a lowered fourth scale degree
. Starting on C, it contains the notes: C, D, E, F, G, A and B. (This is the C Locrian mode, C-D-E-F-G-A-B, with F changed to F. For this reason, the altered scale is sometimes called the "super locrian mode.") It is the seventh mode of the ascending melodic minor scale
. The scale is sometimes spelled with two thirds rather than a flatted fourth scale degree—e.g. C-D-E-E-G-A-B, with E substituting for F. In contrast to the term acoustic scale
, the term "altered scale" almost always refers to this particular mode of the melodic minor, rather than the scale itself. In this sense, the term "altered mode" would be more accurate. The altered scale is also known as the Pomeroy scale (Bahha & Rawlins 2005, 33) (after Herb Pomeroy
(Miller 1996, 35)), the Ravel scale (after Ravel), and the diminished whole-tone scale (due to its resemblance to the whole-tone scale
) (Haerle 1975, 15) as well as the dominant whole-tone scale and Locrian flat four (Service 1993, 28).
The altered scale appears sporadically in the works of Debussy
and Ravel
(Tymoczko 1997), as well as in the works of recent composers such as Steve Reich
(see, in particular, the Desert Music). It plays a fundamental role in jazz, where it is used to accompany altered
dominant seventh chord
s starting on the first scale degree. (That is, the scale C-D-E-E-G-A-B is used to accompany chords such as C-E-G-B, the "dominant seventh flat five" chord. See: chord-scale system
.
The C super locrian scale consists of the notes C D E F G A B C
One way to obtain the altered scale is by raising the tonic of a major scale
by a half step; for example, taking the tonic of the B-major scale, B C D E F G A B
raising the tonic by a half step produces the C altered scale, C C D E F G A C
the notes of which are enharmonic
(identical, in the equal temperament
system) with the notes of the C altered scale.
Like the other modes of the melodic minor ascending, the altered scale shares six of its seven notes with an octatonic
(or "diminished") scale, and five of the six notes of a whole-tone scale, and thus is occasionally referred to as the "diminished whole tone scale." (For example, the altered scale C-D-E-E-G-A-B shares all but its A with the octatonic scale C-D-E-E-F-G-A-B; while sharing five of the six notes in the whole-tone scale C-D-E-G-A-B.) This accounts for some of its popularity in both the classical and jazz traditions (Callender 1998, Tymoczko 2004).
Jazz
Jazz is a musical style that originated at the beginning of the 20th century in African American communities in the Southern United States. It was born out of a mix of African and European music traditions. From its early development until the present, jazz has incorporated music from 19th and 20th...
, the altered scale or altered dominant scale is a seven-note
Heptatonic scale
A heptatonic scale is a musical scale with seven pitches per octave. Among the most famous of these are the major scale, C D E F G A B C; the melodic minor scale, C D E F G A B C ascending, C B A G F E D C descending; the harmonic minor scale, C D E F G A B C; and a scale variously known as the...
scale
Musical scale
In music, a scale is a sequence of musical notes in ascending and descending order. Most commonly, especially in the context of the common practice period, the notes of a scale will belong to a single key, thus providing material for or being used to conveniently represent part or all of a musical...
that differs from the Locrian mode
Locrian mode
The Locrian mode is either a musical mode or simply a diatonic scale. Although the term occurs in several classical authors on music theory, including Cleonides and Athenaeus , there is no warrant for the modern usage of Locrian as equivalent to Glarean's Hyperaeolian mode, in either classical,...
in having a lowered fourth scale degree
Degree (music)
In music theory, a scale degree or scale step is the name of a particular note of a scale in relation to the tonic...
. Starting on C, it contains the notes: C, D, E, F, G, A and B. (This is the C Locrian mode, C-D-E-F-G-A-B, with F changed to F. For this reason, the altered scale is sometimes called the "super locrian mode.") It is the seventh mode of the ascending melodic minor scale
Minor scale
A minor scale in Western music theory includes any scale that contains, in its tonic triad, at least three essential scale degrees: 1) the tonic , 2) a minor-third, or an interval of a minor third above the tonic, and 3) a perfect-fifth, or an interval of a perfect fifth above the tonic, altogether...
. The scale is sometimes spelled with two thirds rather than a flatted fourth scale degree—e.g. C-D-E-E-G-A-B, with E substituting for F. In contrast to the term acoustic scale
Acoustic scale
In music, the acoustic scale, overtone scale, Lydian dominant scale, or Lydian 7 scale, is a seven-note synthetic scale which, starting on C, contains the notes: C, D, E, F, G, A and B. This differs from the major scale in having a raised fourth and lowered seventh scale degree. It is the fourth...
, the term "altered scale" almost always refers to this particular mode of the melodic minor, rather than the scale itself. In this sense, the term "altered mode" would be more accurate. The altered scale is also known as the Pomeroy scale (Bahha & Rawlins 2005, 33) (after Herb Pomeroy
Herb Pomeroy
Irving Herbert "Herb" Pomeroy, III was an influential swing and bebop jazz trumpeter and educator...
(Miller 1996, 35)), the Ravel scale (after Ravel), and the diminished whole-tone scale (due to its resemblance to the whole-tone scale
Whole tone scale
In music, a whole tone scale is a scale in which each note is separated from its neighbors by the interval of a whole step. There are only two complementary whole tone scales, both six-note or hexatonic scales:...
) (Haerle 1975, 15) as well as the dominant whole-tone scale and Locrian flat four (Service 1993, 28).
The altered scale appears sporadically in the works of Debussy
Claude Debussy
Claude-Achille Debussy was a French composer. Along with Maurice Ravel, he was one of the most prominent figures working within the field of impressionist music, though he himself intensely disliked the term when applied to his compositions...
and Ravel
Maurice Ravel
Joseph-Maurice Ravel was a French composer known especially for his melodies, orchestral and instrumental textures and effects...
(Tymoczko 1997), as well as in the works of recent composers such as Steve Reich
Steve Reich
Stephen Michael "Steve" Reich is an American composer who together with La Monte Young, Terry Riley, and Philip Glass is a pioneering composer of minimal music...
(see, in particular, the Desert Music). It plays a fundamental role in jazz, where it is used to accompany altered
Altered chord
In music, an altered chord, an example of alteration, is a chord with one or more diatonic notes replaced by, or altered to, a neighboring pitch in the chromatic scale...
dominant seventh chord
Dominant seventh chord
In music theory, a dominant seventh chord, or major minor seventh chord,is a chord composed of a root, major third, perfect fifth, and minor seventh. It can be also viewed as a major triad with an additional minor seventh...
s starting on the first scale degree. (That is, the scale C-D-E-E-G-A-B is used to accompany chords such as C-E-G-B, the "dominant seventh flat five" chord. See: chord-scale system
Chord-scale system
The chord-scale system is a method of matching, from a list of possible chords, a list of possible scales. The system has been widely used since the 1970s and is "generally accepted in the jazz world today"...
.
The C super locrian scale consists of the notes C D E F G A B C
One way to obtain the altered scale is by raising the tonic of a major scale
Major scale
In music theory, the major scale or Ionian scale is one of the diatonic scales. It is made up of seven distinct notes, plus an eighth which duplicates the first an octave higher. In solfege these notes correspond to the syllables "Do, Re, Mi, Fa, Sol, La, Ti/Si, ", the "Do" in the parenthesis at...
by a half step; for example, taking the tonic of the B-major scale, B C D E F G A B
Enharmonic
In modern musical notation and tuning, an enharmonic equivalent is a note , interval , or key signature which is equivalent to some other note, interval, or key signature, but "spelled", or named, differently...
(identical, in the equal temperament
Equal temperament
An equal temperament is a musical temperament, or a system of tuning, in which every pair of adjacent notes has an identical frequency ratio. As pitch is perceived roughly as the logarithm of frequency, this means that the perceived "distance" from every note to its nearest neighbor is the same for...
system) with the notes of the C altered scale.
Like the other modes of the melodic minor ascending, the altered scale shares six of its seven notes with an octatonic
Octatonic scale
An octatonic scale is any eight-note musical scale. Among the most famous of these is a scale in which the notes ascend in alternating intervals of a whole step and a half step, creating a symmetric scale...
(or "diminished") scale, and five of the six notes of a whole-tone scale, and thus is occasionally referred to as the "diminished whole tone scale." (For example, the altered scale C-D-E-E-G-A-B shares all but its A with the octatonic scale C-D-E-E-F-G-A-B; while sharing five of the six notes in the whole-tone scale C-D-E-G-A-B.) This accounts for some of its popularity in both the classical and jazz traditions (Callender 1998, Tymoczko 2004).
Sources
- Rawlins, Robert, and Nor Eddine Bahha. 2005. Jazzology: The Encyclopedia of Jazz Theory for All Musicians, edited by Barrett Tagliarino. Milwaukee: Hal Leonard. ISBN 9780634086786.
- Callender, Clifton. 1998. "Voice-leading parsimony in the music of Alexander Scriabin." Journal of Music Theory 42, no. 2 ("Neo-Riemannian Theory", Autumn): 219–33.
- Haerle, Dan. 1975. Scales for Jazz Improvisation: A Practice Method for All Instruments. Lebanan, Indiana: Studio P/R; Miami: Warner Bros.; Hialeah : Columbia Pictures Publications. ISBN 9780898987058.
- Miller, Ron. 1996. Modal Jazz Composition & Harmony Advance Music.
- Service, Saxophone. 1993. Saxophone Journal 18
- Tymoczko, Dmitri. 1997. “The Consecutive-Semitone Constraint on Scalar Structure: A Link Between Impressionism and Jazz.” Integral 11:135–79.
- Tymoczko, Dmitri. 2004. “Scale Networks in Debussy.” Journal of Music Theory 48, no. 2 (Autumn): 215–92.