
For two months now, we’ve been investigating
quartal harmony and learning
how to use fourths as building blocks for
our chord voicings, rather than the traditional
thirds. We’ve looked at three-, four-,
and five-note quartal forms across various
string sets and test-driven more than a
dozen grips up and down the fretboard.
In this lesson, we’ll conclude our exploration
by looking at ways to integrate
quartal and tertian (third-based) harmony.
If you missed the previous lessons or want
to review the concepts we’ll be using in this
month’s installment, visit premierguitar.com
and look for “Exploring Quartal Harmony”
and “Crazy Quartal Comping” in the April
and May 2011 issues, respectively.
If you’ve played through the examples
in the last two lessons, you know that
quartal voicings have an edgy, restless
sound. They’re neither major nor minor,
and when played in a sequence, they don’t
suggest the kinds of tension and resolution
we’re used to hearing in, say, blues with
its I-IV-V progressions or mainstream jazz
with its ii-V-I cadences. Because of this,
quartal voicings offer a degree of harmonic
freedom, and they’re particularly handy
when you want to accompany melodic
improvisation without having to follow
common chord patterns.

But most music we hear consists of
thirds-based harmony and some combination
of major, minor, augmented,
diminished, and dominant chords. While
it’s fun to stack fourths, we can’t get
by as musicians on a strict quartal diet.
Wouldn’t it be great if we could bring
the ambiguous, angular sounds of quartal
voicings into the world of traditional tertian
harmony? Fortunately, we can.
And it’s simple—a visual thing. All we
have to do is squint at a standard chord
and see if we can imagine a quartal grip
lurking in its shadow.
Let’s play a game: Can you create a
quartal grip by changing just one note of
a four-note tertian chord? That’s one note
on one string—up or down a half-step or
whole-step. If the other three chord tones
remain the same, it stands to reason that
in most musical contexts, you can substitute
this spiky quartal doppelgänger for its
more conventional sibling.
Fig. 1 shows ten voicings. The left column
consists of standard chords we know
and love, and the right column shows
quartal grips that differ from their adjacent
pals by only one note. For example, look
at the top pair—E7 and E11. The first
chord will be very familiar to most players.
To get the second—which consists of two
perfect fourths (E–A and A–D) topped by
an augmented fourth (D–G#)—you simply
drop E7’s B a whole-step to A.
Download Example Audio 1...
In our previous two lessons, we didn’t
try to name the quartal forms we generated,
simply because we’d left the world
of traditional harmony—and its nomenclature—
to explore a brave new realm
where the old rules didn’t apply. But in
this E11, we have a purely quartal voicing
(E–A–D–G#) that we also can name and
describe in conventional terms. Ah-ha!
Sometimes quartal harmony can insinuate
itself into the world of third-based chords.
Fig. 2 illustrates how easy it is to combine
third- and fourth-based harmony, and
how well these sounds blend. Essentially,
we have an Em7-A progression—a ii-V
in the key of D. But by changing Em7 to
Em11, a one-note alteration, we inject a
sense of mystery to the simple progression
by having it begin with quartal harmony.
Download Example Audio 2...

In
Fig. 3, we use a yet another min11
voicing to color the Vm-IV-I progression
in E Mixolydian.
Download Example Audio 3...

Of course, we’re not limited to minor
substitutions. This “stealth” quartal technique
of modifying tertian chords works
well with dominant chords too—especially
when you want a biting, funky riff, as
in
Fig. 4. Thanks to the tangy E11, we’ve
put some attitude into what would be a
bluesy, yet otherwise pretty tame I7-bVIIIV7
groove in the key of E. Again, one
note makes all the difference between a
ho-hum E7 and a
whoa E11.
Download Example Audio 4...

So far in this lesson, we’ve been smuggling
modified four-note seventh chords
into our progressions. But three-note quartal
clusters work well with tertian chords
too, as shown in
Fig. 5. If you look carefully
at the B11, C#11, and E11 clusters
in this example, you’ll see they’re simply
stripped-down versions of the four-note
E11 fingering shown in Fig. 1.
Download Example Audio 5...

To this point, the goal has been to
demystify quartal harmony—what it is,
how it sounds, and how it lies on the
fretboard. From here, it’s simply a matter
of finding ways to incorporate these bold
colors into your own music.
Next month, we’ll look at another way to
add pizzazz to progressions using something
I call “sparkle” voicings. See you then.

Andy Ellis is a veteran guitar journalist
and Senior Editor at
PG. Based
in Nashville, Andy backs singer-songwriters
on the baritone guitar, and also
hosts
The Guitar Show, a weekly on-air
and online broadcast. For the schedule,
links to the stations’ streams, archived audio
interviews with inspiring players, and more,
visit
theguitarshow.com.