How to construct chords in blues and use them to your own advantage

Now that we’ve gone over some of the scales that we’ll be using in our solos, let’s spend some time on the other half of the equation—chords.

Before we start discussing some of the progressions that we’ll be soloing over, let’s talk a bit about how chords are built (a.k.a. chord construction.)

Simply stated, chord construction involves stacking scale tones to form relative chords, whether basic triads, seventh chords, or extended chords (9ths, 11ths, and 13ths). In this book, we’re going to mostly stick to triads and major, minor, and dominant seventh chords, while introducing a few extended chords.

Triads in blues music

The most fundamental of all chords is the triad. A triad is a three-note chord that can be major, minor, augmented, or diminished in quality. The triads that you’ll most frequently encounter—in this book and elsewhere—are major and minor triads.

The major triad (1–3–5) is built from the root, 3rd, and 5th of the major scale, while the minor triad (1–b3–5) is built from the root, b3rd, and 5th of the minor scale (you can also think of it as a major triad with a lowered 3rd).

The other two triads, augmented (1–3–#5) and diminished (1– b3–b5), can be thought of as alterations of the major and minor triads, respectively. To form an augmented triad, simply raise (i.e., augment) a major triad’s 5th one half step; likewise, to achieve a diminished triad, simply lower (diminish) a minor triad’s 5th one half step.

Below, C major (C), C minor (Cm), C augmented (Caug), and C diminished (Cdim) triads are indicated in notes and tab.

Seventh chord in blues

Although not quite as popular as triads, seventh chords are still found in practically every musical setting, from jazz and blues to country and pop.

Like triads, seventh chords come in several qualities, with major, minor, and dominant being the most popular; unlike triads, however, seventh chords are comprised of four notes. The major seventh (1–3–5–7), minor seventh (1–b3–5–b7), and dominant seventh chords (1–3–5–b7) are built from the root, 3rd, 5th and 7th of the major, minor, and dominant (Mixolydian) scales, respectively.

Below, C major seventh (Cmaj7), C minor seventh (Cm7), and C dominant seventh (C7) chords are indicated in notes and tab.

As you can see, by simply lowering the 7th of the Cmaj7 chord by a half step (one fret), the chord becomes dominant in quality (C7). The distinguishing characteristic of a dominant seventh chord is the presence of both a major chord tone (3rd) and a minor one (b7th).

This major/minor juxtaposition in what gives the blues its distinct, melancholy sound—and why so many dominant seventh chords are used in the music. The minor seventh chord also has a b7th. But what differentiates it from the dominant seventh chord is the presence of a minor 3rd, as well. Any note that is stacked on top of the 7th is considered an extension.

The construction of extended chords in blues

The extended chord family includes 9ths, 11ths, and 13ths, and like seventh chords, extended chords can be major, minor, or dominant in quality. A 9th chord is a seventh chord with a major 9th interval (i.e., the scale’s 2nd raised an octave) stacked on top. An 11th chord is a ninth chord with a perfect 11th (the scale’s 4th raised an octave) on top. And a 13th chord is an 11th chord with a major 13th (the scale’s 6th raised an octave) on top.

Because guitar players are limited to four or five fingers when voicing a chord, it’s general practice to eliminate certain pitches from extended chords. Typically, the first pitch to be jettisoned is the 5th, as it plays no part in defining the chord’s quality (major, minor, or dominant), nor is it an extension.

The next chord tones to go are typically extensions below the one that defines the chord. For example, if you were to play a C13 chord (1–3–5–b7–9–11–13: C–E–G–Bb–D–F–A), you could eliminate the 9th and 11th and still maintain the integrity of the chord because the major 3rd (E), minor 7th (Bb), and 13th (A) are still present, which gives the chord its dominant 13th sound.

Moreover, if you are playing with a bass player and he is holding down the root, you could eliminate the tonic (C) from the chord, too. Below are some common extended chords in the key of C.

Although some pitches have been omitted (as mentioned above), the full chords are spelled out above the notation staff.