Guitar Theory - 4 Note Chords
7ths
Now we go to the 4 note chords. The first is the Dominant 7th. This is the most used 7th chord and most players refer to it only by the name “7th”. This will cause a lot of confusion when you see the technical name “Dominant” 2 or 3 years from now after you’ve been referring to it as a 7th. This is THE blues chord. Almost every blues song written has Dominant 7th chords in it.
The formula is: 1 3 5 b7
EXAMPLE
A(dominant)7th: A C# E G
It looks like this:
Our next chord is the Major 7th:
It’s formula is: 1 3 5 7
EXAMPLE
A major 7th: A C# E G#
It looks like this:
The next commonly used 7th is the Minor 7th.
It’s formula is this: 1 b3 5 b7
EXAMPLE
A minor 7th: A C E G
It looks like this:
There are 4 more 7th chords that you can use. Here are their formulas:
Minor/Major 7th: 1 b3 5 7
Minor 7b5 or Half diminished: 1 b3 b5 b7
Diminished 7th: 1 b3 b5 bb7(double flat: lower 2 half steps)
Augmented 7th: 1 3 #5 7
Besides the naturally occurring triads we studied in the Basic Guitar Theory Lessons, there are also naturally occurring 7ths in every key. As with the triads our chords are named based on the root note’s major scale NOT the scale we are building the chords from. Here they are:
Note: The numbering system above is for the notes as they are in the key scale, not the formula based on the root note. In other words in the Key of ‘C’, the II Minor 7th chord is made of the following notes: D F G C(key of “C” #2,4,6,8).
This a D minor 7th chord; it’s formula is still 1 b3 5 b7. In the key of D of course; the root note’s key.
