a guest post by Christopher Davis Most guitarists are familiar with with the C.A.G.E.D. system of chords and scales. Essentially the whole point of the CAGED system is to say, "Hey, you can play stuff in different positions of the guitar." Which is awesome! But the CAGED system is also useful for figuring out where exactly chords come from. Why do we put our fingers down like this? What notes are contained in a chord? Why are they those specific notes? etc.
It starts with the scale patterns (download pdf). These represent five different major scale patterns that can be used anywhere on the guitar neck. Put the circled, root note on C and you'll be playing in C major. Put it on E and you'll be in E major.
CAGED- Connecting Chords with Scales
For the purposes of this article, we're going to focus on one scale pattern and associated chord. In each scale, there are 7 different notes (scale degrees). As we get to the 8th note in that scale, it's an octave of the first and the notes start over.
Here's a pretty common major barre chord shape with a sixth string root:
This chord can actually said to be descended up the above major scale shape. Here's them both together with the chord highlighted in red.
Mmmm, That's a Tasty Chord Recipe
As we can see above, only certain scale degrees are contained within the major chord: 1, 3 and 5. This is what I call the chord "Recipe." All kinds of chords can have recipes which are all related to the various major scales. However, not all the chords work out as nicely as the major chord above. Some require alterations to notes of the majors scale. We can do this by adding a flat or sharp to the scale degree.
Many guitarists notice that there's only one note difference between a major and minor barre chord.
We can overlay that minor shape onto the scale scale as before.
We find that one of the tones in the minor chord exists outside the major scale. Because of conventual harmony practices we relate that note to the third scale degree(technically, most chords must have a third). Because it's just one fret lower, we call it flat 3 or b3. This makes the chord recipe 1, b3, 5.
Seeing the Numbers
The bonus of understanding what's in your chord is that you can alter it on the fly. Ever seen a great chord like A7#5b9? The suffix to the chord root (A) tells us the data about what's contained in the chord. Here we take a dominant 7th chord and raise the 5 (a 7th chord recipe contains 1, 3, 5, b7) and add in a b9. 9 is the second scale degree up one octave (as in: 1 2 3 4 5 6 7 8(or 1) 9(or 2)-- remember that note names repeat at the 8th scale degree or octave).
Knowing how your chords are put together or literally seeing the numbers lets you alter those chords to suit your needs. But it takes practice to begin to see individual voices of a chord in addition to the whole shape.
Some More Common Chord Recipes
Major- 1 3 5 Minor- 1 b3 5 Dominant or 7- 1 3 5 b7 Major 7- 1 3 5 7 Minor 7- 1 b3 5 b7 half diminished or minor7b5- 1 b3 b5 b7 diminished- 1 b3 b5 bb7 (seventh is lowered a whole step rather than a half, double flat) dominant 9- 1 3 5 b7 2 major 9- 1 3 5 7 2 minor 9 1 b3 5 b7 2
Now the fun part: make up your own chords! Take these chord recipes and figure out scale degrees on the scales (start from 1 on the root, or circled notes and go upwards). And try to invent your own chord shapes. The other option would be to try and figure out the shapes you already know in relation to scales and scale degree numbers.
Christopher Davis is a classical guitar player and teacher based in Tennessee.