Guitar Music Theory 2

This online music theory tutorial will teach you 2 systems to construct guitar chords

1. The first system starts from the major scale.

Construct the major scale with the same root as the chord you want to construct (how to construct major scales).
For example: when you want to create an Am chord, construct the A major scale : A B C# D E F# G#
Find the notes of the major chord : 1 3 5
In our example in the key of A this would be : A C# E
Apply the chord formula on the major chord.
The minor chord formula is 1 b3 5, so the 3rd of the major chord has to be lowered with a half step : A C E

2. The second system involves some memorization and will be explained later in the tutorial.

Now we know how to make chords with 3 different notes, but what about chords with 4 or more notes? Chords with 4 different notes are called seventh chords and are used a lot in jazz and some kinds of pop music. Let's have a look at how to construct seventh chords:

We'll begin with the C major scale again:

C Major Scale C D E F G A B

1 2 3 4 5 6 7

Seventh chords are made the same way as triads : by stacking 3rds on top of the root.
Triads were constructed by stacking 2 thirds, seventh chords are constructed with 3 thirds.

Let's try to construct a chord on the 1 of the C major scale :

C E G B

1 3 5 7

This results in a C major 7 chord (Cmaj7). C to E makes a major third, E to G a minor third and G to B a major third : this structure is typical for major 7 chords.
Chord formula for major 7 chords: 1 3 5 7

The 2nd note of the C major scale :

D    F    A    C

1    b3   5    b7

This results in a D minor chord (Dmin7).  D to F makes a minor third, F to A a major third and A to C a minor third : this structure is typical for minor 7 chords.
Chord formula for minor 7 chords: 1 b3 5 b7

Let's jump to the 5th note of the C major scale :

G    B    D    F

1    3    5    b7

This results in a G dominant 7 chord (G7).  G to B makes a major third, B to D a minor third and D to F a minor third: this structure is typical for dominant 7 chords.
chord formula for dominant 7 chords: 1 3 5 b7

Let's do it on the 7th note of the scale:

B    D     F     A

1    b3    b5    b7

This results in a B half diminished chord (Bm7b5).  B to D makes a minor third, D to F a minor third and F to A a major third: this structure is typical for half diminished chords.
Chord formula for half diminished 7 chords: 1 b3 b5 b7

Here's the list with all the seventh chords of the C major scale: :

Notes Formula Chord Name Symbol

1 C    E    G    B 1     3     5    7 C major 7 Cmaj7

2 D    F    A    C 1   b3     5    b7 D minor 7 Dm7 or D-7 or Dmin7

3 E    G    B    D 1   b3     5    b7 E minor 7 Em7 or E-7 or Emin7

4 F    A    C    E 1     3     5    7 F major 7 Fmaj7

5 G    B    D    F 1     3     5    b7 G dominant G7

6 A    C    E    G 1   b3     5    b7 A minor 7 Am7 or A-7 or Amin7

7 B    D    F    A 1   b3   b5    b7 B half diminished Bm7b5 or Bmin7b5

Next page: part 3 of guitar music theory