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Triad Chord Scales

In this lesson we’re going to learn about triad chord scales. While it’s a pretty basic concept, it’s really useful for applying triads to the guitar fretboard in a way that also provides some musical benefit.

What is a chord scale?

A chord scale is when you take the notes of a scale and use each note to build its own chord. It’s also known as harmonizing a scale. This is done by stacking thirds to create the triads that form the chords. See the Major Scale Chords lesson for a full rundown of the process. Once you have the chords for a scale, you can play them in a scalar fashion up and down the neck. Which brings us to triad chord scales.

Triad chord scales

When applied to triads, chord scales are an effective way to learn triads all over the neck, particularly when applied across all keys. Let’s run through a few examples using the major scale to see how it works.

Major scale triads

When you harmonize the major scale, you end up with three types of triads: major, minor, and diminished. Major triads are formed on the 1st, 4th, and 5th degrees of the scale, while minor triads are formed on the 2nd, 3rd, and 6th. The diminished triad is built from the 7th degree of the scale.

Major Scale Triads
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MajorMinorMinorMajorMajorMinorDiminished

As you may recall, each three note triad can be played three different ways:

  1. Root position (root in the bass note position)
  2. First Inversion (3rd in the bass note position)
  3. Second Inversion (5th in the bass note position)

For linear simplicity of being able to work straight up the fretboard, we’ll work with each position of the triad using different scales. Just note that each of these triad shapes are applicable to all scales.

Triad chord scale, 1st inversion triads (G Major Scale)

We’ll start with the G major scale using the 1st inversion triads on strings 1, 2, and 3. The triad shapes we’ll be using are as follows:

1st inversion triad shapes

Let’s start by noting the G major scale up the neck on string 1.

Notes of the g major scale on the fretboard

If we take this scale and apply the triad for the given scale degree as outlined above, we get the following G major triad chord scale.

G Major Scale Triads
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G MajorA MinorB MinorC MajorD MajorE MinorF# Diminished
G major triad chord scales from root position
G Major Triad Chord Scale
Guitar tab for G major triad scale

Triad chord scale, 2nd inversion triads (D Major Scale)

The 2nd inversion triads give us the following triad shapes:

2nd inversion triad shapes

As you can see, with the 2nd inversion triads on strings 1, 2 and 3, the root note falls on the 2nd string.

Let’s take the D major scale up the neck on the 2nd string.

Notes of the d major scale on the fretboard

Harmonizing the D major scale gives us the following triads:

D Major Scale Triads
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D MajorE MinorF# MinorG MajorA MajorB MinorC# Diminished

When applied to the fretboard we get the following D major chord scale built from 2nd inversion triads.

D major triad chord scales from root position
Guitar tab for D major triad scale

Triad chord scale, root position triads (B Flat Major Scale)

In the root position we have the following triad shapes.

Root position triad shapes

In the root position on strings 1, 2, and 3, the root note falls on the 3rd string. Let’s put the B♭ major scale on the fretboard on the 3rd string.

Notes of the b flat major scale on the fretboard

The harmonized B♭ major scale gives us the following triads.

D Major Scale Triads
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B♭ MajorC MinorD MinorE♭ MajorF MajorG MinorA Diminished

Putting these triad shapes on the fretboard we get the follow chord scale for B♭ major.

B flat major triad chord scales from root position
Guitar tab for B flat major triad scale

Positional chord scales

So far we’ve looked at playing the triad chord scales linearly up the neck. Playing them in this manner focuses on a single voicing for all triads. However, if we play them in a single position, we can utilize all three voicings of the triad throughout the scale. Let’s take the G major example starting with the 1st inversion G major triad.

G major positional triad chord scale diagrams
Guitar tab for G major positional triad chord scale

As you can see, we’re able to use all triad voicings in order to play the triad scale in the same relative position instead of moving horizontally up the neck. This approach can be adapted to any triad starting point. In other words, we can start with the G major triad in the root position or the 2nd inversion and play the scale within that given position.

Additionally, we can play positionally across all string groupings and even use a mix of string groupings for the various triads. This approach provides us with numerous possibilities when it comes to exploring triads all over the fretboard. Work your way around the circle of 5ths and apply chord scales to each key and you have a complete triad practice session.

Wrap up

Triad chord scales are an effective means to practice and apply triads all across the guitar fretboard. They can be applied linearly up and down the fretboard or positionally. Positionally applied triads give you a wealth of options to explore triad relationships across all string groupings and voicings.

AGT book of scales cover

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