How To Construct Chords

This is by no means an attempt to fully explain music theory. However, it can be used as a reference for building simple chords.

The basic music scale is made up of series of 12 notes, each separated by a semitone (S). A tone (T) is 2 semitones. Depending on where you start, the notes look like this:-

A A# B C C# D D# E F F# G G#
B C C# D D# E F F# G G# A A#
C C# D D# E F F# G G# A A# B
D D# E F F# G G# A A# B C C#
E F F# G G# A A# B C C# D D#
F Gb (F#) G Ab (G#) A Bb (A#) B C Db (C#) D Eb (D#) E
G G# A A# B C C# D D# E F F#
etc                      
  • #= sharp, b = flat
  • A# can also be known as Bb
  • C# can also be known as Db
  • F# can also be known as Gb
  • G# can also be known as Ab
  • There is no E#, Fb, B# or Cb

Based on the starting note, these notes can be identified by their position in the scale.

1 b2 2 b3 3 4 b5 5 b6 6 b7 7

Chords are created by selecting certain variations on these positions. Here is a list of the simplest chord:-

major 1 3 5  
minor 1 b3 5  
7th 1 3 5 b7
minor 7th 1 b3 5 b7
major 7th 1 3 5 7
6th 1 3 5 6

So, for instance if we want to work out all of these chords for the scale starting at D, we get:-

1 b2 2 b3 3 4 b5 5 b6 6 b7 7
D D# E F F# G G# A A# B C C#
D major D F# A  
D minor D F A  
D 7th D F# A C
D minor 7th D F A C
D major 7th D F# A C#
D 6th D F# A B

or for G

1 b2 2 b3 3 4 b5 5 b6 6 b7 7
G G# A A# B C C# D D# E F F#
G G B D  
G minor G Bb (A#) D  
G 7th G B D F
G minor 7th G Bb (A#) D F
G major 7th G B D F#
G 6th G B D E

So, by knowing the starting note, and which intervals make up the chord, eg - major = 1-3-5, the notes of any chord can be worked out.