The foundation of the Western musical tradition is the diatonic scale, known best by its "major" and "minor" modes, though there are five other modes of this scale used somewhat less often. The diatonic scale is a specific pattern of intervals, called whole- and half-steps (or more formally, tones and semitones), arranged in a circle. Any of the seven degrees of this circle can be used as a starting position, becoming the tonic of a particular mode, the pattern of which is formed by going around the circle until returning to the tonic.
On a piano, starting on a particular white key and playing up along the next seven white keys yields one of the modes, with a "whole-step" being whenever a black key is skipped and a "half-step" being wherever there is no black key. However, the pattern itself is what defines a mode, and the pattern could be started from any key, skipping or landing on both white and black keys as the pattern dictates; the "white keys only" method simply provides one convenient example of each mode to understand and remember.
In this table, the "2367" column gives the patterns of major (M) and minor (m) seconds, thirds, sixths, and sevenths for each mode; the fourth and fifth degrees are assumed perfect, though the Lydian mode has an augmented fourth and the Locrian mode has a diminished fifth, as noted. This view provides an easy way to construct the modes from any starting key, and to directly compare their properties.
Notice that each sequence in the "Pattern" column features the same sequence as its neighbors above and below, but with the interval at one end (either a Whole- or Half-step) moved to the other end; the sequences at the top and bottom of the list are likewise related. This reflects the circulating nature of the diatonic scale.
While the "major" and "natural minor" modes have been most commonly used, all seven modes of the diatonic scale have been employed throughout history and are still in use today. There are, however, two other circulating seven-tone scales that can be built out of the standard twelve-tone system using only whole- and half-steps, and these scales remain considerably more obscure. In this context, the diatonic scale is known as Heptatonia Prima, in contrast to Heptatonia Secunda and Heptatonia Tertia.
A quick glance at these tables can give a good idea why these patterns haven't often been explored: they exhibit many more augmented and diminished intervals (and resulting chords) than Heptatonia Prima, which makes working with them harmonically considerably more difficult. Tertia even has an augmented sixth in one mode, and (even worse for the tonic chord) a diminished third in its inversion! These are certainly awkward in comparison to Prima.
However, there are clearly a few modes that are relatively straightforward. For example, the MmMM mode of Secunda is also known as the "melodic minor" scale, and has been used regularly. Its inversion, the mmMm mode, is equally stable, though both these modes do feature some augmented and diminished chords, and therefore some skill is required to handle them well. Similarly, the mmMM mode of Tertia features both augmented and diminished chords, but has seen use as the "Neapolitan major" scale.
An exploration of even the most complicated modes could yield interesting results in the hands of an adventurous composer. It is a challenge not often undertaken, and many distinctive works may yet be produced!
On a piano, starting on a particular white key and playing up along the next seven white keys yields one of the modes, with a "whole-step" being whenever a black key is skipped and a "half-step" being wherever there is no black key. However, the pattern itself is what defines a mode, and the pattern could be started from any key, skipping or landing on both white and black keys as the pattern dictates; the "white keys only" method simply provides one convenient example of each mode to understand and remember.
PATTERN | 2367 | MODE | WHITE KEY |
WWHWWWH | MMMM | Ionian (major scale) | C |
WHWWWHW | MmMm | Dorian | D |
HWWWHWW | mmmm | Phrygian | E |
WWWHWWH | MMMM+#4 | Lydian | F |
WWHWWHW | MMMm | Mixolydian | G |
WHWWHWW | Mmmm | Aeolian (natural minor scale) | A |
HWWHWWW | mmmm+b5 | Locrian | B |
In this table, the "2367" column gives the patterns of major (M) and minor (m) seconds, thirds, sixths, and sevenths for each mode; the fourth and fifth degrees are assumed perfect, though the Lydian mode has an augmented fourth and the Locrian mode has a diminished fifth, as noted. This view provides an easy way to construct the modes from any starting key, and to directly compare their properties.
Notice that each sequence in the "Pattern" column features the same sequence as its neighbors above and below, but with the interval at one end (either a Whole- or Half-step) moved to the other end; the sequences at the top and bottom of the list are likewise related. This reflects the circulating nature of the diatonic scale.
While the "major" and "natural minor" modes have been most commonly used, all seven modes of the diatonic scale have been employed throughout history and are still in use today. There are, however, two other circulating seven-tone scales that can be built out of the standard twelve-tone system using only whole- and half-steps, and these scales remain considerably more obscure. In this context, the diatonic scale is known as Heptatonia Prima, in contrast to Heptatonia Secunda and Heptatonia Tertia.
HEPTATONIA SECUNDA
PATTERN | 2367 |
WWHWHWW | MMmm |
WHWHWWW | Mmmm+b5 |
HWHWWWW | mmmm+b4+b5 |
WHWWWWH | MmMM |
HWWWWHW | mmMm |
WWWWHWH | MMMM+#4+#5 |
WWWHWHW | MMMm+#4 |
HEPTATONIA TERTIA
PATTERN | 2367 |
HWWWWWH | mmMM |
WWWWWHH | MM#M+#4+#5 |
WWWWHHW | MMMm+#4+#5 |
WWWHHWW | MMmm+#4 |
WWHHWWW | MMmm+b5 |
WHHWWWW | Mmmm+b4+b5 |
HHWWWWW | mbmm+b4+b5 |
A quick glance at these tables can give a good idea why these patterns haven't often been explored: they exhibit many more augmented and diminished intervals (and resulting chords) than Heptatonia Prima, which makes working with them harmonically considerably more difficult. Tertia even has an augmented sixth in one mode, and (even worse for the tonic chord) a diminished third in its inversion! These are certainly awkward in comparison to Prima.
However, there are clearly a few modes that are relatively straightforward. For example, the MmMM mode of Secunda is also known as the "melodic minor" scale, and has been used regularly. Its inversion, the mmMm mode, is equally stable, though both these modes do feature some augmented and diminished chords, and therefore some skill is required to handle them well. Similarly, the mmMM mode of Tertia features both augmented and diminished chords, but has seen use as the "Neapolitan major" scale.
An exploration of even the most complicated modes could yield interesting results in the hands of an adventurous composer. It is a challenge not often undertaken, and many distinctive works may yet be produced!
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