Watch the 9th, 11ths, 13ths online guitar lesson by Robbie Calvo from Guitar Interactives
PRINCIPLE 15 - CHORD EXTENSIONS
As you know, we can add extensions of a 9th, 11th or 13th to our 7th chords. These extensions become chord tones. Chord extensions add flavor to our 7th chords but do not change the quality and function of the chord.
Let’s add each extension to our chords so that you can hear the effect they have on the basic 7th.
Let’s explore where natural 9ths and minor 9ths occur on our diatonic chords as this will be very powerful in making sure you keep your extensions as diatonic chord extensions...in other words, only using notes derived from the G Major scale.
Major 9ths occur naturally on the I - II - IV - V - VI chords and minor 9ths occur on the III - VII chords.
It should be noted that adding a natural 11th to the I chord, GMajor is going to sound incredibly dissonant due to the fact that the 3rd and now the 4th both exist in the chord. In practice and real world applications any 11th chord with a major 3rd will have a raised 4th (11) to reduce this dissonance. Raising the 4th/11th on the I chord takes the chord. out of our G Major scale however, so please remember that. Raised or augmented 4ths on the IV chord are naturally occuring so no alterations are needed.
Perfect 11th’s will occur naturally on the I - II - III - V - VI - VII chords and will be naturally augmented on the IV chord.
It should also be noted that 13th’s will also be subject to whether they are are major 13th or minor 13ths. Major 13th occur on the I - II - IV - V chords and Minor 13ths occur on the III - VI - VII chords in the scale.
A great way to visually see what extensions are Major , Minor , perfect or augmented is to utilize the 7 major scale patterns across the fingerboard using a 6th string root note.