Chord Construction - Learn Guitar Theory Part 2

Chords are constructed by using notes taken from the major scale. There are formulas we can use to find the notes in any chord. In part 1 we took a look at the major scale and learnt how each scale note is numbered from 1 to 7 and then 8 to 15 once we go past the octave. The notes in the C major scale for instance would be numbered like this for the two octaves.

C  D  E  F  G  A  B  C  D  E  F  G  A  B  C
1  2  3  4  5  6  7  8  9  10 11 12 13 14 15

Chords are based on the root of their corresponding major scale. In other words, All C chord formulas use the C major scale, D chords use the D major scale and so on. Now let's take a look at major chord formulas. The list below shows the chord construction formulas.

• Major chord - 1 3 5
• Major 7 chord - 1 3 5 7
• Major 9 chord - 1 3 5 7 9
• Major 11 chord - 1 3 5 7 9 11
• Major 13 chord - 1 3 5 7 9 11 13

Using these formulas we can work out what the notes are for major chords in C.

• C major - Formula 1 3 5 - Notes C E G
• Cmaj7 - Formula 1 3 5 7 - Notes C E G B
• Cmaj9 - Formula 1 3 5 7 9 - Notes C E G B

And so on.

One thing that you might notice is the numbers 10, 12, 14 and 15 are very rarely used. This is too involved for our purpose, remember this is only the stuff you need to know, we don't want to go into deep theory. All you need to know is the formula 1 3 5 10 (C E G E) will just be named a major chord, not a major 10, even though, technically speaking that's exactly what it is. The same goes for the others. 1 3 5 12 (C E G G) will also just be named a major chord and not a major 12, etc.

Minor Chords

Minor chords follow the same idea as major except some of the notes will be flattened. Here is a list of minor chord formulas.

• Minor chord - 1 b3 5
• Minor 7 chord - 1 b3 5 b7
• Minor 9 chord - 1 b3 5 b7 9
• Minor 11 chord - 1 b3 5 b7 9 11
• Minor 13 chord - 1 b3 5 b7 9 11 13

As we did with major chords, we can now use these formulas to work out what the notes are for minor chords in C.

• C minor - Formula 1 3 5 - Notes C Eb G
• Cmin7 - Formula 1 3 5 7 - Notes C Eb G Bb
• Cmin9 - Formula 1 3 5 7 9 - Notes C Eb G Bb D

And so on.

And now just in case you are confused, the observant among you would have noticed that Eb and Bb don't belong in the C major scale. This is correct. The chord formulas are always based on the major scales remember. There are other methods and formulas that can be used, for instance, we could use chord formulas for minor chords that are based on the minor scales. This gets into heavy music theory however, and the major scale reference not only always applies, it's the most common.

Don't forget, chord formulas are based on the same root note as the corresponding scale. Just for clarity, here's how we would use this method for E chords.

E major scale...

E  F# G# A  B  C# D# E  F# G# A  B  C# D# E
1  2  3  4  5  6  7  8  9  10 11 12 13 14 15

• E major - Formula 1 3 5 - Notes E G# B
• Emaj7 - Formula 1 3 5 7 - Notes E G# B D#
• Emaj9 - Formula 1 3 5 7 9 - Notes E G# B D# F#

And so on...

You can see that armed with just these chord construction formulas, it's possible to find the notes for any chord by looking up the major scale notes. Below are more formulas for constructing the most popular chord types.

Dominant Chords

• Seventh - 1 3 5 b7
• Ninth - 1 3 5 b7 9
• Eleventh - 1 3 5 b7 9 11
• Thirteenth - 1 3 5 b7 9 11 13

Diminished Chords

• Diminished - 1 b3 b5
• Half Diminished (m7b5) - 1 b3 b5 b7
• Diminished Seventh -1 b3 b5 bb7

Next ... Scale Formulas