There are many ways to voice chords on guitar. One of the coolest is to steal a technique from choral, horn, and string arranging that yields a rich, molten sound. And it’s easy, once you know the basic rules.
It’s tempting to view a chord progression as a sequence of fixed note formations that we grip and release, one after the other. This makes sense on a tactile level because, after all, it‘s what our fingers are doing. But if we only think of chords as discrete grips, we may overlook how each one is connecting to its neighbor. And when we don’t pay attention to these harmonic transitions, we can wind up lurching around the fretboard, playing voicings that don’t dovetail musically. This isn’t necessarily a bad thing. In fact, some styles demand sliding up and down the neck with barre or power chords to create a jagged effect. But, as we’ll discover in this lesson, there are other ways to navigate a progression.
One approach involves making the smallest possible shifts between the notes in one chord and the next. This technique yields a flowing, molten sound, and it’s well worth exploring.
Rules of Engagement
The concept—which, incidentally, we’re borrowing from choral, horn, and string arranging—is to have the notes in one chord move by either a half-step or whole-step to the notes in the subsequent chord. Occasionally, we interrupt this stepwise motion with a leap of a minor third (three half-steps), but that’s the largest move we make. Sometimes, one of the notes remains the same as we switch chords. This common tone acts as sonic glue, binding adjacent voicings, even as they change.
It’s fun to visualize this process as moving beads on wires. In other words, imagine each chord tone is a bead that either stays put or shifts up or down on its string by one, two, or three frets (a half-step, whole-step, and minor third, respectively) to morph into the next voicing. It’s a game: Can you play a progression without breaking these strict rules?
So we can clearly picture the note-to-note movement, let’s keep things simple and stick with three-note voicings on the top three strings. Most of the chords we’ll play in this lesson contain four or more notes in their full form, but we’re going to cherry-pick three that allow us to follow our bead game rules.
For starters, play through the voicings in Ex. 1 to loosen up your hands and get familiar with the fingerings we’ll soon stitch into a progression. Many of these will be old friends, but some—D7 and A9, for example, in grids 2 and 3—might be new.
As you fret each of these chords, notice how three do double duty, depending on where they’re positioned: A7 and Ebdim (grids 1 and 8), D7 and Ebdim7 (grids 5 and 6), and Dm and D6 (grids 9 and 11). This “shared shape” phenomenon happens because we’re selecting a subset of a chord’s available tones. (If we were to fret the chords in their entirety, we’d spot their physical differences.) Expert rhythm guitarists routinely use multi-purpose fingerings to craft their parts. It takes time to master such musical sleight of hand, but the payoff is huge.
Let the Games Begin
Now it’s time to put our rules into action by playing Ex. 2, a 12-bar blues progression in the key of A. As you change the first two chords, watch those beads shift when you move from A7 to D7. Check it out: On the 1st string, the top note, C#, drops a fret to C. On the 2nd and 3rd strings, each note moves up two frets, (G–A and E–F#, respectively). Excellent! We’ve created contrary motion, which serves to draw listeners into this chord change.
If you peer closely at the A7–A9–A7 changes in measures 3 and 4, you’ll see common tones (for instance, the 2nd-string G occurs in all three voicings), two whole-step moves, and a minor-third leap. Nice and tight—so far, so good.
The A7–D7 shift (measures 4 and 5) is very economical, consisting of a common tone and two half-step drops. Conversely, the D7–Ebdim7 change incorporates three upward, minor-third leaps. This parallel movement is immediately balanced by the contrary motion in the Ebdim7–A7 change across measures 6 and 7.
At this point, you’ve seen enough to know how the bead game works. As you complete the progression, take a moment to evaluate each chord change and track its note-to-note movement. You’ll find that right through the end of measure 12, every change consists of common tones and half-step, whole-step, or minor-third moves. The only exception is when we reach the end of measure 12 and jump back to the top to repeat the progression. Because measure 12’s E7 and measure 1’s A7 share the same fingering, try sliding from E7 to A7 for a dramatic break from our otherwise frugal motion.
By the way, the A7–Ebdim–Dm–A7 move in measure 8 makes a dandy turnaround or intro. With little effort, you’ll be able to insert it into a blues or even a fingerpicked folk song.
The next step is to incorporate the bead game concept into your playing. We’ll be using this technique in upcoming lessons, but to really own it, you’ll need to explore it yourself. One way to get started is to transpose this lesson’s progression down an octave, placing it on lower strings. Though the chord shapes will look different—and you’ll find more than one place to fret them—the common tones and half-step, whole-step, and minor-third moves will all remain the same.
Next month, we’ll look at a trick for generating voicings that are tailor-made for a hybrid, plectrum-and-fingers picking technique.
Stepwise motion. When a melodic line moves up or down in half- or whole-steps (distances of one or two frets, respectively), it employs stepwise motion.
Contrary motion. When two lines move in opposite directions—one ascending while the other descends—they produce contrary motion. This can also occur during a chord change when one voice moves up as another moves down.
Diminished triads and diminished 7 chords. Every chord type has a formula that’s derived from a major scale. (For more details on scale and chord formulas, see the November 2010 Rhythm & Grooves.) The formula for a diminished triad is 1–b3–b5, or the first, lowered third, and lowered fifth tones of a major scale. We add a fourth note to generate a diminished 7 chord, which has a formula of 1–b3–b5–bb7.
To identify the notes in a diminished chord, simply apply the appropriate formula to a parallel major scale. For example, to unpack a Cdim or Cdim7, we start with a C major scale (C–D–E–F–G–A–B–C) and then run the corresponding formulas. This yields C–Eb–Gb (Cdim) and C–Eb–Gb–Bbb (Cdim7). Sonically, a bb7 note is the same as a 6, so many musicians choose the latter as a kind of shorthand when spelling a diminished 7 chord. Using this informal approach, we’d identify Cdim7’s component notes as C–Eb–Gb–A. When two notes sound the same but are named differently—such as A and Bbb—they’re considered enharmonic equivalents.