A Guide To Guitar Chords

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

 

Guitar music theory part 3  Next page: part 3 of guitar music theory