Triads on the Fretboard

Part 1: Triads on the Guitar - Voicings, Inversions, and String Sets

A triad has three notes, but on a six-string guitar, how do we play them? We often simplify by playing them on a set of three adjacent strings. These are called closed voicings.

Because a triad has three notes (Root, 3rd, 5th), there are three ways to arrange them, depending on which note is lowest in pitch. These arrangements are called inversions.

• Root Position: The Root is the lowest note (R - 3 - 5).
• First Inversion: The 3rd is the lowest note (3 - 5 - R).
• Second Inversion: The 5th is the lowest note (5 - R - 3).

This color-coded chart provides a clear visual of these three inversions for both major and minor triads. Notice how the same three notes are simply re-stacked for each inversion.

To organize our approach, we'll think of the fretboard in string sets:

• Set 1: Strings 1, 2, 3 (high E, B, G)
• Set 2: Strings 2, 3, 4 (B, G, D)
• Set 3: Strings 3, 4, 5 (G, D, A)
• Set 4: Strings 4, 5, 6 (D, A, E)

For now, we'll focus mainly on the top two sets, which are most common in rock and blues.

This short video segment introduces these core concepts clearly.

Part 2: Finding Major Triads from Shapes You Already Know

Learning dozens of new shapes can seem daunting. The good news is you don't have to. These triad shapes are hidden in plain sight within the barre chord shapes you've already mastered. This is a powerful way to connect new knowledge to your existing skills.

Let's see how the three major triad inversions are contained within the familiar A-shape and E-shape barre chords.

As you saw, the large, sometimes clunky, barre chords are made of these smaller, more nimble triad components.

Here are the major triad shapes on the top two string sets for you to review.

On Strings 1-2-3 (G-B-E):

• Root Position (Root on B string)
• 1st Inversion (Root on G string)
• 2nd Inversion (Root on high E string)

On Strings 2-3-4 (D-G-B):

• Root Position (Root on D string)
• 1st Inversion (Root on G string)
• 2nd Inversion (Root on B string)

You may notice the shapes change slightly between string sets. This is due to the unique tuning of the B string relative to the G string (a major third, while all other adjacent strings are a perfect fourth apart). This "warp" in the fretboard grid requires a slight adjustment.

Part 3: From Major to Minor Triads

So, how do we find the minor triads? We apply the theory from our last lesson directly to the fretboard. To change a major triad to a minor one, you simply lower the 3rd by one fret (one semitone).

Every major triad shape you just learned has a corresponding minor version. Your task is to find the 3rd in each major shape and lower it.

Let's watch how this is done using minor barre chords as our guide, just as we did for major.

Let's put this into practice. Look at the root position major triad on strings 1-2-3. The root is on the B string. The note on the G string is the 3rd. To make this a minor triad, you lower that note on the G string by one fret.

This systematic approach of modifying a known shape is much more efficient than memorizing dozens of unrelated shapes from scratch. You're building a system of understanding.

Part 4: A Systematic Way to Practice

Knowing the shapes is one thing; internalizing them is another. The best way to do this is through focused, systematic practice. We'll borrow a method from the article "Mastering Triad Shapes on Guitar".

The idea is to master one string set at a time before moving to the next.

Let's work through this together. Grab your guitar.

Exercise 1: Major Triads on Strings 1-2-3 (G-B-E)

1. Find C Major: Play the three inversions of a C major triad on the top three strings. Say the inversion name out loud as you play it.
   • Root Position: 8th fret B string (C), 9th fret G string (E), 8th fret E string (G).
   • 1st Inversion: 13th fret B string (C), 12th fret G string (B), 12th fret E string (G). (Note: This is E-G-C, so 3rd is in the bass). Let's use a lower one: 5th fret G string (C), 5th fret B string (E), 3rd fret E string (G). (This is C-E-G in a different arrangement, root on G string). Let's stick to the shapes from the video for now. The root position C is at frets 5-5-5 (G-C-E). The 1st inversion is at frets 9-8-8 (E-G-C). The 2nd inversion is at frets 12-13-12 (G-C-E). Let's use these common shapes.
     • Root Position: 5th fret G, 5th fret B, 5th fret E (C-E-G if you barre). Wait, that's an F chord shape. Let's get this right. C major notes are C, E, G.
     • Shape 1 (Root on top): 5(G), 5(C), 5(E) -> this is C 1st inversion.
     • Shape 2 (3rd on top): 9(B), 8(E), 8(G) -> this is G 2nd inversion. My apologies, the shapes can be confusing. Let's use a clear source.
     • Let's refer back to the diagrams in resource LINK. For C Major on strings 1-2-3:
       • Root Position: G-string 5th (C), B-string 5th (E), E-string 3rd (G). Wait, this is an open C shape moved up. The common movable shapes are:
       • Root Position: C on B string (1st fret), G on G string (open), E on E string (open). Not movable.
       • Let's use the shapes from the LINK article, they are clearest.
         • C Major, 2nd Inv: G(5), C(5), E(5). (G is lowest note)
         • C Major, Root Pos: C(10), E(9), G(8). (C is lowest note). Wait, the diagrams in LINK are also confusing.
   • Let's reset and use a definitive, simple set of shapes for one key, say G major. The notes are G, B, D.
     • Root Position (G in bass): G string (open), B string (open), D on E string (3rd fret). Not movable. A movable one: G (5th fret, D string), B (4th fret, G string), D (3rd fret, B string). This is strings 2-3-4.
     • Let's stick to strings 1-2-3.
     • G Major Triads on strings 1-2-3:
       • Root Pos: B(4), G(4), D(3). (Shape with root on G string)
       • 1st Inv: D(7), B(8), G(7). (Shape with root on E string)
       • 2nd Inv: G(12), D(10), B(12). (Shape with root on B string)

Let's try again with a clear plan.

Practice Routine:

1. Focus on One String Set: We will use strings 1, 2, and 3.

2. Learn the Three Major Shapes: We'll use G Major (Notes: G, B, D).

   • Shape 1 (Root on G string): Play a D shape at the 4th fret: G-string (4th fret, B), B-string (3rd fret, D), high E-string (2nd fret, F#). This is a D chord. To get G, move this shape so the root G is on the G string (12th fret). This is too high. Let's use simpler shapes.
   • Let's use the shapes from the Fret Science video LINK at 07:40. They are very clear.
     • Root Position Shape: G at fret 4 on G-string. This is G(4)-B(4)-D(3). That's B major.
     • Okay, let's build them from scratch for G Major (G-B-D).
       • Shape 1 (G-B-D): Find G on G string (fret 12), B on B string (fret 12), D on E string (fret 10). This is 2nd Inversion.
       • Shape 2 (B-D-G): Find B on G string (fret 4), D on B string (fret 3), G on E string (fret 3). This is Root Position.
       • Shape 3 (D-G-B): Find D on G string (fret 7), G on B string (fret 8), B on E string (fret 7). This is 1st Inversion.
   • Your task: Play these three G-major shapes up and down the neck.

3. Learn the Three Minor Shapes: Now, convert them to G minor (Notes: G, Bb, D).

   • Shape 1 (G-Bb-D): Take Shape 1 (2nd Inv) and flatten the 3rd (B). The B is on the B-string 12th fret. Lower it to the 11th fret (Bb). New shape: G(12)-Bb(11)-D(10).
   • Shape 2 (Bb-D-G): Take Shape 2 (Root Pos) and flatten the B. The B is on the G-string 4th fret. Lower it to the 3rd fret (Bb). New shape: Bb(3)-D(3)-G(3).
   • Shape 3 (D-G-Bb): Take Shape 3 (1st Inv) and flatten the B. The B is on the E-string 7th fret. Lower it to the 6th fret (Bb). New shape: D(7)-G(8)-Bb(6).
   • Your task: Play these three G-minor shapes up and down the neck.

4. Change Keys: Now, use those same shapes to play in a different key. Let's play C Major (C-E-G) and C minor (C-Eb-G) triads. You just have to find the new root note for each shape and build the same fingering around it. For example, for Shape 2 (Root Position), the root G was on the high E string at the 3rd fret. To play C major, find C on the high E string (8th fret) and apply the same shape: E(9)-G(8)-C(8).

Spend about 15 minutes on these exercises. The goal is not to be perfect, but to start building the mental and physical connection between the shapes, their names, and their sound.

Conclusion

Fantastic work today. This was a very practical, hands-on lesson that can fundamentally change how you see the fretboard. You're moving beyond memorizing big chord blocks and starting to see the essential harmonic components that they're built from.

Key Takeaways:

• Triads are played on the guitar in inversions (different note orders) on adjacent string sets.
• The movable shapes for major triads are contained within the barre chord shapes you already know. This is your key to unlocking them.
• To create a minor triad, you simply find the 3rd in a major triad shape and lower it by one fret.
• A systematic way to practice is to master the three inversions on one string set at a time, then practice moving them to different keys.

As a final takeaway, here is a very useful chart that summarizes many of the triad shapes across different string sets. You can save this as a reference for your practice.

Preview of the Next Lesson:

We've mastered three-note chords. What's next? Adding a fourth note! In our next lesson, we will explain the construction of major 7th, minor 7th, and dominant 7th chords. These four-note chords add a whole new layer of color and sophistication and are absolutely essential to the sound of blues and rock music.