The Music Theory Behind Modal Scales
Throughout the post, I’ll be explaining what are modes and how you can use them; how you can make chords to emphasize that mode; and compare how they sound differently from each other - the different shades of major and minor modes.
So, for starters, let me clarify what a mode is. While a scale can be defined as being a series of notes arranged in order of pitch within one octave, modes are actually cyclic permutations of that same scale. The difference is that we choose to consider a different root for that scale and then proceed with the same notes and pitch order arrangement in order to generate a greater variety of sonorities.
That said, the following modes are inversions of the major scale, being the major scale a mode as well. In fact, we get the relative minor scale from one of its inversions; the 6th inversion, starting and finishing in A and still using the same notes.
This means that each inversion brings in a distinct colour or feel because of where the half-steps are positioned. Each major or minor mode is respectively referenced against the major or minor diatonic scale and that said, a mode is a musical scale that has its own set of melodic and harmonic characteristics and behaviours. We will be looking at the modes present in the tonality of C Major. The intervallic structure of these modes is used to build the very same modes on every other tonality:
Again, notice how all the modes have the same notes (the white keys on a piano) because they are scale inversions of the C Ionian mode or C major scale. In effect, this means that for each tonality, we have seven different natural modes that go with it.
Major and Minor Modes Compared
Ionian - Audio 1
Lydian - Audio 2
Mixolydian - Audio 3
The major scale (Ionian) has half-steps between the 3rd / 4th and 7th / 8th degree. When compared, the Lydian and Mixolydian modes present some similarities with the major scale; the Lydian mode now has a raised 4th and the Mixolydian mode has a flattened 7th degree. Each mode sounds differently and in order to make it so, one will have to focus on these actual differences to bring forth the colour of the chosen mode:
Now, the scale we compare the minor modes to is the minor scale (Aeolian) and it has half-steps between the 2nd/ 3rd and 5th / 6th degree. The Dorian mode is distinguished by having a raised 6th and the Phrygian mode now has a flattened 2nd degree:
Dorian - Audio 4
Phrygian - Audio 5
Aeolian - Audio 6
The Locrian mode could be considered a minor mode, although its diminished 5th interval makes it more useful to play over diminished chords where it won’t clash against the perfect 5th present in both major and minor chords. More into that further ahead but here is how Locrian mode can sound:
Locrian - Audio 7
As a final reminder; your modal melodies should emphasize the characteristics that set the mode apart from the major or minor mode references; Ionian and Aeolian, respectively. If what distinguishes the Dorian mode is the major 6th, then you should pay a special attention to this note in the minor context.
For a more in depth post about how you can create and use modal harmonies in your music , follow this link.
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