Extending Triads

The fundamental chord in western music is the triad which contains the chord tones: 1 3 & 5, where tonality is determined by the 3rd scale degree.

There are four triad types which are determined by 3rd and 5th chord tone:

1. Major
2. Minor
3. Diminished
4. Augmented

With these four types of triads we can add extensions such as 7th, 9th, 11th and 13th chord tone to create more sophisticated sounding chords commonly found in blues and jazz music.

Tonality

When it comes to playing extended chords, unlike a piano player having ten fingers at their disposal, guitar players have to accomodate extended chords to work within the limits of four fretting fingers.

Major

The Major triad can be extended to build to types of Major chords:

1. Major 7th (Maj7) - 1 3 5 7
2. Dominant 7th (dom7 / 7) - 1 3 5 ♭7

Here are some commonly used extension shapes found within the CAGED system.

Position 1 - E Shape

Emaj

1

3

2

Emaj7

2

1

3

Edom7

1

2

Position 2 - D Shape

Dmaj

2

3

1

Dmaj7

2

2

2

Ddom7

3

1

2

Position 3 - C Shape

Cmaj

1

2

3

Cmaj7

2

3

Cdom7

1

4

2

3

Position 4 - A Shape

Amaj

3

2

1

Amaj7

3

1

2

Adom7

3

2

Position 5 - G Shape

Gmaj

3

1

2

Gmaj7

2

Gdom7

1

Minor - E Shape

The Minor triad can be extended to build to types of Minor chords:

1. Minor 7th (min7 / m7) - 1 ♭3 5 ♭7
2. Minor Major 7th (minMaj7) - 1 ♭3 5 7

Position 1

Emin

3

2

Emin7

2

Position 2 - D Shape

Dmin

1

3

2

Dmin7

2

1

3

Position 3 - C Shape

Cmin

2

1

3

Cmin7

1

4

1

3

Position 4 - A Shape

Amin

1

3

2

Amin7

1

2

Position 5 - G Shape

Gmin

1

3

Gmin7

4

1

3

2

Diminished

The Diminished triad can be extended to build to types of Diminished chords:

1. Half Diminished 7th (min7♭5 / m7♭5) - 1 ♭3 ♭5 ♭7
2. Diminished 7th (dim7)- 1 ♭3 ♭5 ♭♭7

Augmented

The Augmented triad can be extended to build to types of Augmented chords:

1. Augmented 7th (aug7) - 1 3 ♯5 7