1. The six qualities of the chord
Modern harmony uses 6 classified chords :
- Major chords
- Minor chords
- Dominant chords
- Half diminished chords
- Diminished chords
- Suspension chords
Each of them includes natural extensions coming from the overtone serie resonating above the root.
Note : Modern harmony does not use the overtones above the N°13, except those placed 1 octave above the first thirteen.
When used, these natural extensions create an additional tension on the basic perfect triad. So, when an extension having an odd number is far away from the root, the resulting tension is important.
More tensed than :
More tensed than :
The most common extensions in pop and jazz music are :
(Overtone number and corresponding extension)
n° 7 major 7th
n° 9 minor 9th
n° 11 augmented 4th = augmented 11th
n° 13 augmented 5th = minor 13th
n° 15 major 7th
n° 17 minor 2nd = minor 9th
n° 19 minor 3rd = augmented 9th
n° 21 perfect 4th = perfect 11th
Each of the six chord qualities is not supposed to accept all these extensions. For example, the minor chord cannot have a minor 9th :
The terms tension and relax are important in the arranging structure.
In fact, all music needs an alternation of these 2 steps, on a melodic, dynamic and structural point of view.
2. The closed position
A chord is in closed position when its constitutive notes are included inside an interval of 1 octave :
C maj 7 C maj 7 6/9
Note : In pop and jazz music, the closed position is mostly used with a parallel "section" writing.
3. The open position
A chord is in "open" position when its constitutive notes are vertically placed over an octave.
Unlike the closed position, the open position brings the following notes to us :
a. The conterpoint writing ( horizontal ), the independance and leading of the voices have a big importance
b. The open position needs a minimum of 3 voices and perfectly fits instruments belonging to the same family or not
c. Like the closed position, the notes that can be kept or deleted remain the same