Understanding Chord Structures
The combination of three or more notes is a chord. Three note chords are called
Open String Chords
In Chapter 5 you learned the chords C, G, and G7 in first position. Below are more major chords made in first position. All of these are made with open strings. These chords will be called by these names throughout the book.
Now that you're familiar with the chords, you'll learn how they are built.
Triads
There are four types of triads: major, minor, augmented, and diminished, which are built by piling major thirds and minor thirds on top of each other in different combinations. You can “spell” the four types of triad chords this way:
C maj |
C-E-G |
maj 3rd min 3rd |
C min |
C-E-G |
min 3rd maj 3rd |
C aug |
C-E-G |
maj 3rd maj 3rd |
C dim |
C-E-G |
min 3rd min 3rd |
Most chord structures are a variation on these four triads. FIGURE 7-13 gives you an example of how these triads can be played on the guitar.
On the guitar, these simple chords are not always spelled this way. For example, you can mix up the order of the notes, and instead of playing C-EG, you can play G-C-E. You can also double notes. An E maj triad is spelled E-G. -B, for example, but it is usually played as a full chord E-B-E-G.-B-E.
It's not really important now to know these structures inside out. Instead, learn the chord forms on the chord diagrams. Try to figure out where other triads can be played on the guitar and write them down for yourself.
Seventh Chords
Four-note chords are called seventh chords. They generally have much more color and they sound more interesting than triads. Furthermore, they are the basis of all standard repertoires of tunes. To make a seventh chord, add either a major third or a minor third to one of the four triad forms. Doing this, you get five basic seventh chords, with other chords being variations on these five.
In the key of C, the five are variations of these:
C maj7 |
C-E-G-B |
|
C7 |
C-E-G-B |
(also called a dominant 7) |
C min7 |
C-E-G-B |
|
C min75 |
C-E-G-B |
(also written Cø7 or C half diminished) |
C dim7 |
C-E-G-A |
(usually called B double flat, but here known as A, which enharmonically it is) |
As you've seen, you can make chords up by piling thirds on top of each other. Another way to look at chords is to build them from the tones of a scale (major or minor — it doesn't matter).
Here's a major scale: |
C |
D |
E |
F |
G |
A |
B |
C |
Put numbers underneath: |
1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
Now use roman numerals: |
I |
II |
III |
IV |
V |
VI |
VII |
VIII |
A chord can be built by choosing every other note in the scale and then altering it if necessary:
C major |
7 1-3-5-7 |
C7 |
1-3-5-7 |
C minor 7 |
1-3-5--7 |
C minor 75 |
1-3-5--7 |
C diminished |
1-3-5--7 |
On the piano keyboard, it's easier to play these chords as they're spelled out here. However, on the guitar that isn't the case. A C major 7 chord, for example, is often played on the guitar and spelled C-E-G-B, or C-G-B-E.
If you spend some time working on understanding how chords are built, you'll soon be able to build your own. For example, if you know how to play a C major 7 chord, and suddenly you are confronted with C major 7. 5, you just need to play a C major 7 shape, figure out which note is the fifth of the chord, and raise it up a fret (semitone) to make the .5 part of this chord.
You learned earlier that there are five basic seventh chords. That's true, but there are seven more chords that are variations on these five. Here are the twelve:
C major 7 |
1-3-5-7 |
C7 |
1-3-5-7 |
C minor 7 |
1-3-5-7 |
C minor 75 |
1-3-5-7 |
C diminished 7 |
1-3-5-7(6) |
C major 75 |
1-3-5-7 |
C major 75 |
1-3-5-7 |
C75 |
1-3-5-7 |
C75 |
1-3-5-7 |
C minor/major 7 |
1-3-5-7 (C minor major 7) |
C6 |
1-3-5-6 |
C minor 6 |
1-3-5-6 |
To see the definitive book on all things guitar chords, check out The Everything Guitar Chords Book, by Marc Schonbrun. It's an accessible book with easy-to-follow diagrams that lead you through guitar chords from the most basic to the most complicated chords used by today's musicians.
Think about this: a minor 6 chord, and a minor 75 chord are the same thing, although they will have different root notes: C minor 6 = A minor 75. (A root note is the note from which the chord is built.)
