Beyond the Basic Blues: Explore Variations on the 12-Bar Form on Ukulele

BY CHRISTOPHER DAVIS-SHANNON | FROM THE FALL 2024 ISSUE OF UKULELE

The three-chord, 12-bar form is generally our first foray into the world of blues, but in reality it is only the tip of the iceberg in learning the style. The blues itself is not just one entity but a genre, tonality, and musical form all tied into each other. Armed with a few chords and a blues or pentatonic scale under their fingers, many folks don’t know where to look for inspiration next. In this lesson, I’ll show you some pathways to explore in taking your blues further from these starting points. 

The Eight-Bar Form

While the 12-bar blues may be the most common form, the second most popular is its eight-measure cousin. This is often overlooked, as the chord changes aren’t quite as easily pinned down as the 12-bar form. That said, most variations are based around the three chords that we are accustomed to—the I, IV, and V. A few examples of this short form include “Trouble in Mind,” “Ain’t Nobody’s Business If I Do” (see Fred Sokolow’s arrangement on page 40 of the Fall 2024 issue), and “Nobody Knows You When You’re Down and Out.” While these tunes all have their own charm, let’s take a look at the chords to Big Bill Broonzy’s “Key to the Highway,” as shown in Example 1.

As always, we’ll be starting on the I chord (C) but moving right away in the second measure to the V7 chord (G7), a common sequence in an eight-bar blues. This brings us right to the IV chord (F7). You can think of this change much like moving to the IV chord in the second four measures of a 12-bar blues, simply condensing the harmony. This pattern follows bringing us back to the I chord, followed by the V7 and then a quick turnaround to the top of the form. 

As you play through this example, keep in mind how the chord changes are reminiscent of the 12-bar form you are already familiar with.

Put a Little Jazz in Your Blues

Since the beginning of New Orleans jazz, musicians have been using the 12-bar blues as a vehicle for improvisation. Over the years, jazz artists have breathed new life into those humble three chords. Much like with the eight-bar blues form, there are nearly infinite variations and chord substitutions we can use in a jazz blues. Having just a few in your bag of tricks can help to spice up an arrangement or add new ideas to a solo.

As depicted in Example 2, for simplicity’s sake, we’ll keep the first four bars of our progression the same as the typical blues 12-bar form, but once we get the IV chord the fun can begin. Instead of staying on the IV for two measures we’ll move up to a #iv diminished seventh. Note that in moving between the IV and the #ivdim7, all of the notes remain the same except the root. This means you can always add a diminished seventh chord to substitute for any chord a half step below.

The F#dim7 chord brings us neatly back to our I chord, which immediately moves to the VI7 (A7). This sound is pushing our ears to a progression found frequently in jazz—the ii–V–I—which will substitute for our typical V7 chord. Much like with our diminished chord, we can put in our back pocket that the ii–V progression can typically be substituted for a V7 chord.

Moving on Over to Minor

A blues doesn’t always have to be constructed of dominant seventh chords. Minor variations of the blues are as old as the form itself. Take a look at the iconic songs of Skip James to get a taste of this tonality. Much like the jazz-blues and eight-bar forms, the minor blues can take many different turns along the way, from George Gershwin’s “Summertime” to “St. James Infirmary.” Example 3 shows one of the more common minor blues progressions, as used by jazz legend John Coltrane in his composition “Mr. P.C.”

The basic form is very similar to that of the typical major 12-bar blues, taking all
of the dominant seventh chords and turning them into minor sevenths. The real fun comes in the last line. We start off on an Ab7, which serves as a tritone substitution for the expected ii chord (Dm7). This provides a nice chromatic movement to the V (G7). If we change that Ab7 to an Abmaj7, we have the form to B.B. King’s “The Thrill is Gone.”

Lose the Chords and Play Some Riffs

What are chords but a group of notes played at once? With this in mind, we can create an accompaniment to a blues using only individual notes while still outlining the chords. This is a great way to break up the monotony when you are playing through the form of a 12-bar shuffle over and over again. 

Our basic shuffle rhythm is swung eighth notes, and we’ll use that as our foundation to build the riffs seen in Example 4. Starting on the root of the I chord (C), we’ll jump up an octave and then walk down to the seventh (Bb). On beat 4, we’ll add an eighth-note triplet incorporating the final notes of the chords, sliding into the third (E) and ending on the fifth (G).

Move this pattern up the neck to start on the fifth fret for the IV chord (F7), jumping up the octave (F) and then walking down to the seventh (Eb). Finally, move everything up two frets for the V chord (G7). This simple riff not only propels the rhythm of the song but gives us the full harmonic picture.

Do the Rumba 

The shuffle and the slow blues with a triplet feel are probably the two most familiar ways to play a blues, but there are plenty of other styles to explore. There has always been a cross-pollination of Latin rhythms in blues, from the habanero of “St. Louis Blues” to Bo Diddley’s clave-inspired rhythms. In early R&B, rock and roll, and blues, the rumba was another popular style, adapted from a Cuban dance rhythm. While the shuffle and slow blues both come from an underlying three feel, or swung eighth notes, the rumba gives us a straight eighth note with unique accents.

You can hear different versions of this feel on Albert King’s “Crosscut Saw” or Elvis Presley’s “Hound Dog.” Much like with Ex. 4, we can create a line to outline the chords and rhythm. The key to internalizing this rhythm (Example 5) is the rest on beat 2 and the second note coming in on the second eighth note of the beat. Try sliding into that third note of the pattern and hammering on the final note of the pattern to help the rhythm really groove.

These are only a few ways you can begin to step outside the constraints of the basic 12-bar blues. There are countless harmonic tricks and grooves to explore in this diverse genre. Don’t let yourself get trapped in the same old patterns; open your ears to the masters and see where you can take the blues.