Beef up your knowledge of everything from the basic 12-bar blues form to more jazz-influenced progressions—and even a few 9-bar blues.
• Understand basic variations of both major and minor 12-bar blues forms.
• Learn how to emphasize the IV chord by using ii-V progressions.
• Create movement and interest with tritone substitutions.
To successfully participate in a jam session, whether it’s a formal session or just some friends getting together to pick in the living room, you’ve got to know tunes—or at least the chord progressions to those tunes. This is true of any style of music, including the blues. The focus of this lesson will be on the essential chord progressions you’re expected to know as a blues rhythm guitarist. We’ll survey chord patterns that every aspiring blues guitarist needs to know, so if you’re just getting started with the blues, this lesson should serve you well.
Let’s start off with the most common blues progression: the 12-bar form. Countless songs—in many styles—are based on this structure. Fig. 1 shows its basic form. Roman numerals indicate the quality of the chord (i.e., major or minor), as well as the position the chord occupies in the key. For example, if we’re in the key of A, the I chord is A, the IV chord is D, and the V chord is E. Uppercase Roman numerals indicate a major chord and lowercase Roman numerals indicate a minor chord. The benefit of learning a progression this way is it’s not locked to a specific key. This makes it easier to transpose the progression to a new key—you simply need to know the key you’ll be playing in and that becomes your I chord.
It’s common to move to the IV chord in the second measure and then back to the I chord in measure three. This is referred to as a “quick change.” If you’re jamming on a blues tune you’re unfamiliar with, keep your ears open because not all tunes employ the quick change.
A turnaround usually occurs in the 11th and 12th measures of the progression. These two measures set things up to bring you back to the top of the form. The turnaround ends with the V chord, and this creates tension. The ear wants to hear the resolution to the I chord, which it gets when the form starts over.
Now that we’ve laid the foundation for a basic 12-bar progression, let’s explore ways to embellish it. By the time we work through these variations, you’ll be able to negotiate everything from a simple blues to its jazzier adaptations. Fig. 2 shows a basic 12-bar blues with the quick change in the key of A. Both these examples serve as a starting point for the variations we’ll discuss from this point on.
For a moment, let’s focus on a few variations in the turnaround. The first one, shown in Fig. 3, is a I–IV–I–V turnaround in the key of A.
The next variation (Fig. 4) will prepare you for those situations when the bandleader calls for a 12-bar blues with a ii-V (pronounced “two-five”). The ii chord is a minor chord—indicated by the lowercase Roman numeral—built off the second note in the key. These last four measures of the form can be plugged into either of the first two examples we discussed. When this variation is used, the turnaround typically changes to include the ii-V as well. It has a strong pull to I, therefore it works well in a turnaround.
To vary the progression further, we’ll add the VI chord in the eighth measure (Fig. 5). This chord creates a pull to the ii chord we introduced in the previous example.
We can also incorporate the VI chord into the turnaround as shown in Fig. 6. This creates the common I–VI–ii–V progression.
In Fig. 4, we inserted the ii-V progression into measures nine and ten, as well as in the turnaround. Remember the ii-V has a strong pull toward the I chord. Because of this, we can place a ii-V in front of a particular chord we want to emphasize.
One of the characteristics that separates the 12-bar blues progression from others, and delivers what we’ve become accustom to hearing as “blues,” is the movement to the IV chord in the fifth measure. By viewing the IV chord as a temporary I chord and placing the corresponding ii-V before it, we harmonically emphasize the “new” I chord (which in the overall progression is really the IV chord). Play through Fig. 7 and listen to how the chord in the fifth measure (D7) is reinforced by the Em7–A7 that precedes it.
Here’s another chordal embellishment to the 12-bar form: In measure six, insert a diminished chord based on the #4 of the key. Fig. 8 shows measures five through seven of the 12-bar form with this snazzy enhancement.
Let’s put it all together. Fig. 9 includes all of the embellishments we’ve examined so far. To add some harmonic variety, I’ve included 13th chords in this example.
Fig. 10 brings us to the tritone substitution. Without going into great theoretical detail, the tritone substitution replaces one chord with another that has its root located a tritone (three whole-steps) or b5 away. It doesn’t matter whether you count up or down to get to the b5 because a tritone splits an octave exactly in half. In the following example—used over the last four measures of the 12-bar form—C13 is the tritone substitution for F#7 (VI), and Bb13 is the tritone substitution for E7 (V).
“Stormy Monday” Changes
A survey of common 12-bar blues progressions would not be complete without the inclusion of the “Stormy Monday” changes. The classic T-Bone Walker tune is a must-know, and the progression in Fig. 11 shows how it’s most commonly played. The most notable difference between this progression and the basic 12-bar blues occurs in measures seven and eight with the ascending and descending minor chords. For variety, I’ve written this example in the key of G and included 9th chords.
Blues guitarists frequently use chromatic approaches when performing this piece. For more details on this concept, as well as musical examples that illustrate it, check out “Uptown Blues,” another lesson in PG’s Style Guide series.
Minor Key 12-Bar Blues
Up to this point we’ve examined blues progressions in major keys. Now let’s shift our focus to the minor blues progression. The basic minor 12-bar blues is very similar to its major counterpart, except that—you guessed it—the progression is built around minor chords!
In Fig. 12, we use a V7 or V7(#9) in measures nine and 12 to arrive at a very common version of the minor blues.
The progression in Fig. 13 uses the bVI chord in the ninth measure, which then moves to the V7 in the 10th measure. Notice how the V7(#9#5) creates smooth voice-leading. You’ll find this change in the last four measures of the progression.
Now, we have all the pieces to play the classic B.B. King minor blues, “The Thrill is Gone.” This tune includes the bVI, however, instead of being a dominant 7, it’s played as a major 7. The sweeter sound of the major 7 provides cool harmonic variety. Fig. 14 presents the progression in the original key of B minor.
As with the major 12-bar blues, ii-Vs can be incorporated into the minor blues. When this occurs, the ii becomes a min7b5. Blues with minor ii-Vs are often found on the jazz side of the blues. Fig. 15 is a minor blues with minor ii-Vs.
Let’s shift our attention to some 8-bar progressions. Two variations we’ll discuss can be found in “Key to the Highway” and “Sittin’ On Top of the World”—popular standards every blues guitarist needs to know. In Fig. 16, you’ll find the 8-bar variation for “Key to the Highway.”
Fig. 17 offers a fingerstyle arrangement of the progression. Like the 12-bar form, the last two bars contain the turnaround. Feel free to insert your preferred turnaround in the last two measures.
Listen to the following Ray Charles version of “Sittin’ On Top of the World.” This version leans more towards the jazzy side of blues and incorporates many of the harmonic moves we introduced in the 12-bar section. You’ll find the Roman numeral analysis of this progression above the chord symbols in Fig. 18.
Not all blues tunes fit neatly into a 12- or 8-bar form. In fact, we’ll close by looking at a common treatment of “Sittin’ On Top of the World” that’s nine measures long. The first variation is based on Howlin’ Wolf’s classic version.
This 9-bar variation appears in Fig. 19. When performing this tune, guitarists commonly include a specific melodic phrase—which follows the vocal line—in measure seven. This example includes the chords that will work against this melodic line.
Check out Robert Cray playing the tune in the following video. Notice how Fig. 20 incorporates many of the chord substitution we’ve discussed so far.
Hopefully you can see that with a few basic progressions—and a handful of tweaks—you can arrive at many blues variations that range from simple to more complex. Not all of the substitutions are appropriate at all times. Take your cues from the tune itself, along with the stylistic feel you’re going for. A key element to all of this is to get it in your ear—you need to be able to intuitively hear all of these variations. This skill will allow you to learn songs from recordings and also quickly hear and adapt to anything thrown your way in a real-time playing situation.