The Rule of Three

A couple of days ago, while taking a break during a jam, I started on the topic of triads with an old friend of mine. I soon realized that he didn’t quite understand what I was talking about, so I picked up an acoustic guitar and tried to show him. This inspired me to write this article and make the video that accompanies it.

Triads are the building blocks of chords. But what are they really? To the uninitiated, they can be a little confusing. Let me break it down by starting with the C Major chord and C Major scale.

As with all major scales, it is made up of 7notess, starting with the root note, which is also known as the 1 position. The root note for the C Major scale, as you may well have imagined, is C. There are few different positions to play that scale on the fretboard, but for our purposes we are using the position starting at the third fret, fifth sting. For ease of playing the remainder of the scale, we play the 1 position with our number 2 finger (the middle finger).

C Major Scale

Each one of those positions represents a note: 1 = C; 2 = D; 3 = E; 4 =F; 5 = G; 6 = A; and 7 = B. The 8 position is the octave, meaning C in the next highest register. Please note that there are no sharps or flats in the C Major scale as it is the starting point on the circle of fifths.

The C Major chord is composed of a major triad, 1, 3, 5. If we refer to the above description, that means the C Major chord is made up of the Root C, the third E, and the fifth G. In this case, the G is the third string (the G string) played open.

C Major Chord

The same holds true for the G Major scale. This scale is one fifth higher on the circle of fifths so there will be one sharp note. The note that is sharpened is the F, which happens to be one position before the previous scale, the C Major scale. The F# is the 7 position of the G Major scale. Therefore, 1 = G; 2 = A; 3 = B; 4 = C; 5 = D; 6 = E; 7 = F# (sharp); and 8 being the octave.

G Major Scale

The G Major chord is also made up of a major triad. The one position, as always, is the root note – G in this case. The third is the B; and the fifth is the D note. The D is the fourth string (D string) played open. The third and second string are also played open so that the G and B are repeated a second time. The third finger is placed on the first string, third fret. Since the first and sixth strings mirror each other, this means this also a G note. In the G Major chord, in this position, the root G is played three times, in different positions on the fretboard.

G Major Chord

The D Major scale is two positions higher on the circle of fifths, meaning that two notes in this scale are sharp,

D Major Sclae

The 1 position is the root note D. The second position is an E note. The third position is F# (carried over from the G Major scale). The fourth is a G note. The fifth is an A. The sixth is a B. The seventh is a C#, which happens to be one fifth before our previous scale, the G major scale.

The pattern repeats itself down the fretboard, but we’ll stick these three examples for now.

The D Major chord is also composed of a major triad. The one position, as always, is the root note – D in this case. The third is an F#; and the fifth is an A.

D Major Chord

The chord patterns shown above are the open chords. These chords can also be played as barre chords in at least two other ways on the fretboard, and the pattern is the same, where they are made up of a major triad.

This knowledge will help you in the future as you learn to improvise and solo. Knowing the structure of the chords you are hoping to solo over will improve your soloing by making it more closely matched to those chords, making the notes you play as you solo more logical and therefore, more melodic. It will also help you play these same chords in other patterns on the fretboard, making your playing a little more unique than simply using standard chord patterns.

Please click on the link below for the video that accompanies this article.

Please follow the links below for a more advanced look at major triads.


  • Incredible Chord Finder, 2nd Edition, Hal Leonard Corp.
  • Incredible Scale Finder, Hal Leonard Corp.
  • Music Theory for Dummies, by Michael Pilhofer and Holly Day, Wiley Publishing Inc.

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