There are seven notes with different names in a major scale e.g.
C, D, E, F, G, A, B
However we usually state that there are eight notes in the major scale, as we tend to start and finish a scale on a root note e.g.
C, D, E, F, G, A, B, C
...to give it resolution.
The second C is the same note, in that it is also a C, however it has a higher pitch than the one we started on, as it is in the next octave - and in that way it is different.
This explains how C2 and C9 are different chords - yet have the same notes (C, D, E, G and C, E, G, D).
It's a lot like how 'NUB' and 'BUN' relate to each other (same components, different order).. …and is also why C13 is not a C6.
So, to summarise, take a major scale - I'll use the example of G major - repeat it and number it as follows:
| G | A | B | C | D | E | F# | G | A | B | C | D | E | F# | etc |
| 1st | 2nd | 3rd | 4th | 5th | 6th | 7th | 8th | 9th | 10th | 11th | 12th | 13th | 14th | etc |
Take the 1st, 3rd and 5th notes, and we have a basic major chord:
G B D = G major, normally written as G
If you want a minor chord flatten the 3rd:
G Bflat D = G minor, normally written as Gm
For a 2nd chord, add the 2nd:
G A B D = G second, normally written as G2
G A Bflat D = G minor second, normally written as Gm2
For a 4th, add the 4th:
G B C D = G major fourth, normally written as G4
G Bflat C D = G minor fourth, normally written as Gm4
If you want to create a sus chord, suspend the 3rd and add the 2nd or the 4th in it's place:
G A D = Gsus2
G C D = Gsus4
NOTE: The lack of a 3rd means that these are neither major nor minor - and in that way they are similar to a power chord (which consists of 1st and 5th only)
So there are several chords that are neither major nor minor. This results in a group of chords that are great to use if you want to change what's going on, because they are very 'non-committal'.
So there are several chords that are neither major nor minor. This results in a group of chords that are great to use if you want to change what's going on, because they are very 'non-committal'.
To create a major seventh, add the seventh note to the major chord:
G B D F# = G major seventh, normally written as G triangle by hand - or Gmaj7 onscreen
To create a minor seventh, add the flattened seventh note to the minor chord:
G Bflat D F = G minor seventh, normally written as Gm7
To create a dominant seventh, add the flattened seventh note to the major chord:
G B D F = G dominant seventh, normally written as G7