Maybe you’ve worked to build a solid foundation of music theory, yet need to connect a few more dots in order to feel confident with how the various elements fit together and how to create music with them. In this lesson we study the fundamentals of diatonic harmony to understand the theory, then apply it to the fretboard on guitar to build chords and use them in progression.
First, my congratulations! You have arrived at the last lesson of this series. What you’ve accomplished is no small feat. In our previous lessons, you’ve studied elements of pitch and rhythm, worked on understanding key and time signatures, achieved greater fretboard familiarity, and tackled numerous assignments and exercises that required a significant expenditure of time, patience, and focus. The purpose of this lesson is to draw together the pieces of what we’ve discussed thus far, apply them as we look at some principles of diatonic harmony, and get you using what you’ve learned to play and write music.
This is another dense lesson, so I recommend a few deep breaths, earplugs if you’re someplace noisy, and caffeine or some exercise if you’re not fully alert. Once you’re ready, have at it!
BUILD MAJOR KEY TRIADS
Western tonal music is fundamentally about tension and release. There are countless ways to navigate between these areas, traversing shades of tension and degrees of resolve through harmonic progression—the movement of one chord to another.
As you have seen, every key has an associated scale. Every scale degree has an associated triad. We have derived some diatonic chords in the blues lesson, but let’s take a closer look now, starting with the major mode. The tonic, or chord built on the first scale degree, represents the place of stable musical repose. The dominant, built on the fifth degree, is its counterpart—the chord of tension. The subdominant chord is built on the fourth degree and often precedes the dominant in harmonic progression. While tonic, subdominant, and dominant chords all have specific meanings (the I, IV, and V, respectively), each chord in a key has a function that falls into one of these categories.
Let’s take a look at the chords that result from building a triad on each scale degree. Write out a C major scale, as shown in Example 1 (below). We will spell each chord upwards from the root. Start with scale degree 1 to find the tonic chord, C. C is the root of the chord. Skip one scale degree to get the third, E. Skip another scale degree for the fifth, G. Remembering what you learned in the previous lesson, look at the intervals to determine the quality of the chord: C to E is a M3, and C to G is a P5, so the tonic chord in the key of C major is—you guessed it—a C major triad. Seems intuitive enough, but now you know why.
Move to the second scale degree. D is the root. Skip up a scale degree to get the third, F, and another to get the fifth, A. Now analyze the intervals upwards from the root: a m3 and a P5, or a D minor triad. Continue that procedure for all the scale degrees (Example 2). The chord quality associated with each scale degree will be the same across all major keys, so it’s well worth it to fix them in your mind. With only one exception, all chords within the major mode are major or minor. The chord built on the seventh scale degree—in this case B—is diminished, as B to D is a m3, and B to F is a dim5.
REPEAT WITH MINOR KEY CHORDS
Using the same process as in Ex. 2, we’ll build the triads of A minor, the relative minor of C major, as shown in Example 3. Like in the major mode, the chord qualities you’ve derived will be the same across all minor keys. As you might have deduced, relative keys share the same notes and therefore the same chords. Context and progression are what allow us to hear them as independent keys.
Often the minor mode will borrow the leading tone (seventh scale degree) from the parallel major mode (e.g., A minor borrows the note G# from A major, as conveyed in Example 4a). The leading tone is a very active note, as the half step between it and the tonic creates a strong pull upwards toward resolve. By adopting the leading tone from A major, the dominant chord in the minor mode becomes major and gravitates more strongly toward the tonic—compare the progression with the natural seventh, as in the first measure of Example 4b, to that with the raised seventh in the next measure.
FORM SOME MAJOR KEY PROGRESSIONS
Now let’s look at some common progressions and transfer them to the fretboard, using just the top four strings. Not only are these voicings useful aesthetically (play them, and hear what I mean), but approaching chords this way will force you to focus on the concepts, rather than falling back on familiar shapes.
Begin by building all the chords in G major (Example 5). Then take the ubiquitous I–IV–V–I progression, found across the spectrum of genres: rock, blues, country, folk, soul, indie, classical/baroque, to name just a few. Example 6a shows the progression starting in the third position. Example 6b moves it up to the fifth position, Example 6c to seventh position, and Example 6d to tenth position. As you play through these chords, use your harmonic knowledge to identify their notes, find them on the neck, and relate them to the harmony. Don’t just go by the tablature, as that defeats the purpose of the exercise and robs you of the experience of putting your efforts into action. Notice how each individual voice moves to the next—take your time so you can really see and hear it. These small movements (also called voice leading) make for smoothly connected chord transitions. Next, work through the ii–V–I, one of the most common progressions in jazz and popular music in general, as shown in the key of G in Examples 7a–7d.
CLOSE OUT WITH MINOR PROGRESSIONS
Let’s move to the key of E minor. First, write out the E minor scale and associated chords (Example 8). Example 9a shows the i–iv–v–i progression (Em–Am–Bm–Em). As you build these minor chords, notice their close relation to their major counterparts. Find the third(s) in each voicing and move it up a half step, transforming the triad from minor to major. For instance, take the first Em voicing of Ex. 9a, move the Gs on strings 1 and 4 up by one fret each (to G#), and you’ll recognize your E major triad.
Example 9b, also in E minor, is identical to Ex. 9a, except that it uses the major V chord (in this case, B). Make your way up the neck, independently discovering the chord voicings in each position for the progression. Finding them for yourself with the knowledge you’ve been building is hugely beneficial.
Example 10 is yet another progression in E minor, this time using the leading tone of D#, resulting in the harmonies viiº and V. To get that diminished chord better in your brain and under your fingers, remember that it’s just a minor triad with a lowered fifth. So you can always start with the more familiar minor chord and move the fifth(s) down by a half step.
For the last set of chords, try another very typical major progression that mixes major and minor diatonic triads: I–vi–ii–V–I, this time in the key of A major. Write out the scale and chords first on your own. You’ve already worked through ii–V–I movements in Ex. 7, so it’s just a question of adding the vi chord. Example 11 will get you started, and then you can proceed independently. Once you have these chord progressions down, try them in every key. Work on building the chord forms on the middle four strings and bottom four strings. Then try repeating the process with different chord progressions.
These should not be seen as exercises to go through a few times and then considered checked off an educational to-do list. Spend time with them, and be patient. Try exercises like these for an hour a day for a month, and watch your chord vocabulary, fluency, and neck familiarity skyrocket.
Then write your own progressions. A lot of them. Doing so engages you actively and creatively, deepens the learning, and results in the reward of something that is musically yours. I bet you’ll discover many new ideas in the process, and that’s the point—when done with the right intention and attitude, study increases inspiration and provides tools for the freer expression of ideas.
I thank you for letting me be a small part of your musical journey in this series. Music has one of the highest benefit-to-risk ratios out there—it has the power to delight, inspire, comfort, and unite. Yet the most common downside is that certain types might not appeal to you aesthetically. So be fearless as you learn and grow, knowing you’ll harm no one. Invest in your musical fluency, cultivate your imagination, develop your sound, and create from your highest self. You never know how you might affect the world positively.
As I send you off on the next phase of your journey, I want to give you my recommendations for what I consider essential reading material.
Tonal Harmony, Stefan Kostka, Dorothy Payne, Byron Almen. My go-to reference for clear, concise, comprehensive harmony and theory.
Zen Guitar, Philip Toshio Sudo. You’ll find no theoretical or guitar-specific exercises, but rather a wealth of wisdom to prime your attitude and approach along the lifelong path of music.
Peak: Secrets from the New Science of Expertise, Anders Ericsson and Robert Pool. Well-researched, with solid scientific data, this book convincingly dispels many myths and unhelpful notions about talent and expertise.
The Obstacle Is the Way, Ryan Holiday. Based in Stoic philosophy, this provides wisdom on how we perceive and confront challenges.
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