Monday, December 13, 2010

December 13, 2010: Upper Voices and the First Four Heptatonic Systems from the Harmonic Continuum

We spoke earlier of the Harmonic Continuum. In its purest form the Harmonic Continuum is the overtone series. Without repeating notes in higher octaves and adjusting for equal temperament, the first seven tones from the overtone series gives us this arpeggio:

R,3,5,b7,9,#11 and 13.

This is also the arpeggio derived from the fourth mode of the Melodic Minor scale, if arranged in a series of ascending thirds.

Fourth Mode of Melodic Minor scale: R,2,3,#4,5,6,b7
Same mode in ascending thirds (Extended arpeggio): R,3,5,b7,9,#11,13

Seven note scales and modes, when placed in a ascending thirds, mirror the trajectory of the overtone series, even if their intervallic patterns vary from it. If we take a mode, using Dorian for example here, and look at it and listen to it in a series of ascending thirds we see where the upper voices come from. 2, 4 and 6 become 9, 11 and 13.

Dorian mode: R,2,b3,4,5,6,b7

Looking at it in thirds we see the first three notes create a minor arpeggio. If they are played simultaneously they are a minor triad.
R,b3,5.

The first four notes give us a minor seventh (m7) arpeggio/chord.
R,b3,5,b7

Five notes in thirds from the root is a minor ninth (m9) arpeggio/chord.
R,b3,5,b7,9

Six notes, minor eleventh (m11)...
R,b3,5,b7,9,11

All seven give us a minor thirteenth (m13).
R,b3,5,b7,9,11,13

Because the improvising accompanist often will voice a chord sparsely to imply certain harmonies it’s possible that, for example, a Dm13 may be voiced, in ascending order, C,F,B, which is b7,b3,13. If it’s necessary to have the entire harmony played, the full symbol Dm9,11,13 should be used, keeping in mind that certain instruments, including guitar and vibes, will have to arpeggiate the chord to some extent to effectively sound all seven tones.

Heptatonic Systems

When defining a harmony that may appear obscure to an improviser in the midst of moving chord changes, i.e., Csus b2, or simply wanting to imply a seven-tone tertian harmony, it is an option to use modal symbols. In the chart below the first four systems of seven tones (heptatonic) with their respective seven modes each are illustrated. This provides 28 modal symbols.

Bars 2, 3 and 4 of Ex. 1 and 1a (bottom of blog page) demonstrates this with the notated figures on the lower staves.

Rather than apply C as the root of each modal naming, each mode below has the tone of its root in the context of its Heptatonic System as its modal root so the structure of each system and mode is clearly shown.

Modal Symbols

We will start with the first four Heptatonic Systems - Major, Melodic Minor, Harmonic Minor and Harmonic Major.

For each system we will list the modal and modal symbol like this:

Mode (Ionian, Dorian, Phrygian, etc.)
Modal Symbol (major, dor, phryg, etc.)


Major System

Ionian
C major

Dorian
D dor

Phrygian
E phryg

Lydian
F lyd

Mixolydian
G mixo

Aeolian
A aeol

Locrian
B locr

Melodic Minor System

Melodic Minor
C mel min

Phrygidorian
D dor b9

Lydian Augmented
Eb lyd #5

Overtone
F lyd b7

Harmonic Mixolydian
G mixo b13

Aeolian b5
A aeol b5

Super Locrian
B sup locr

Harmonic Minor System

Harmonic Minor
C harm min

Thircrian
D locr nat13

Major Augmented Eb maj #5

Dorilydian
F dor #11

Spanish Gypsy
G span gyp

Lydian #9
Ab lyd #9

Super Locrian Diminished
B sup locr dim

Harmonic Major System

Harmonic Major
C harm maj

Dorian b5
D dor b5

Super Phrygian
E sup phryg

Lydian Melodic Minor
F mel min #11

Mixolydian b9
G mixo b9

Lydian Augmented #9
Ab lyd #5, #9

Phrygian Diminished
B phryg dim

Since, at this time, most improvisors only have a familiarity with the first three Heptatonic Systems, I would suggest having an explanation of any additional modes from any system beyond the first three accompanying any charts of your compositions that contain melodies and harmonies from these systems.

Next: We view the structure of these Heptatonic Systems in even more detail and introduce Symmetrical Scales.

Copyright © 1993-2010 Jack DeSalvo

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