Diatonic Guitar Thinking
In this guitar lesson we are going to go over diatonic thinking as it relates to the guitar. Diatonic thinking means thinking about all of the notes, chords, scales and arpeggios that occur naturally in a given key without any altered notes. To get this idea across, we will go through all of the chords in the key of G major by playing what is called a chord scale.
Let’ s start by reviewing the G major scale. The notes in a G major scale are G A B C D E and F#. For the purpose of this lesson we will focus on diatonic chords and pentatonic scales in the key of G major. Every note in the G major scale has a chord and a pentatonic scale that goes with it. The 1st 4th and 5th note of every major scale will have a major chord and a major pentatonic scale associated with them. The 2nd 3rd and 6th note of every major scale have a minor chord and a minor pentatonic scale associated with them. The 7th note of every major scale has a diminished chord and a minor flat five pentatonic scale associated with it.
Now that we know which chords are major, minor, and diminished in any major key let’s take it one step further and learn what 7th chords are in a major key. When you build chords in a key there are certain chords that are major, minor, and diminished. If you build 7th chords for the same notes in any major key, there will be certain chords that are major 7th, minor 7th, dominant 7th, and half diminished. Let me write out the 7th chords in the key of G for you so that you can see what I mean.
1. G major 7th
2. A minor 7th
3. B minor 7th
4. C major 7th
5. D dominant 7th
6. E minor 7th
7. F# minor b5 or F# half diminished
As you can see the 1st and 4th note in a any major scale have major 7th chords that go with them, the 2nd 3rd and 6th notes have minor 7th chords that go with them, the 5th scale degree has a dominant 7th chord to go with it, and the 7th note has a minor flat 5 or half diminished chord associated with it. This is always the case in any major key. If you were to play all of these chords starting on the G major 7th chord all the way up to the F# minor b5 you would have a chord scale.
Try writing down every major key that you know. Take your major 7th, minor 7th, dominant 7th, and half diminished chords and play the chord scales for every major key that you have written down. This is a great exercise for you to start memorizing what chords are in what keys.