~ 13 ~ Thirteen ~

'up an octave, our diatonic 6th now a 13th, is a potent spice in the diatonic pie ...'

'... the key point of summit and balance of the Americana arpeggio ...'



In a nutshell. Our Thirteen is simply Six up a full octave. That Six is home to the diatonic relative minor group of pitches should illuminate its potential importance as Thirteen. Thirteen is almost always thought of as a chord tone. A color tone that sits atop various combinations of 7, 9, and 11 above major and minor triads. By including a 7th we get chord type and a new level of theory potentials. Examine the letter name pitches in C major to locate 13. Example 1.

scale degrees
two octave C major scale

Wide space between 1 and 13. These 13th chords are pretty colossal in interval distance. As the chart shows we're closing in on our second octave closure. Thus our root position voicings which follow will barely get off the lowest E and A strings.

So why a summit? Well in nearly all of our American sounds and styles, our chordal colortones reach their highest popular point or summit numerically at 13. We'll look at 14, 15 and even a new idea for #15, but these types of numerical designations are entirely absent in our written American music, we just never see them. So we in a sense top off the arpeggio at 13. So what can be seen from this summit?

The essential balance. As the Six / Thirteen pitch is also home to our relative minor position within our diatonic scale, an interesting color transformation occurs when we add this hue to our chord voicings. It just seems that whenever we 13 add into a chordal mix, the music takes on a heightened sense; whether it's a stronger pull of the swing, or the heartfelt longing of the minor 9/13 chords, or just a bit brighter as in the jump blues '6' chords, finding a chord with just a bit more joyous for the last hold of an arrangement.

At the summit. An example of this idea of a summit point between our Yin / Yang dichotomy, hear and sense how easily our V13 chord, here as G13, slips towards both the relative tonic chords of A minor and C major. Example 2.

Soften the tonic colors. By softening the tonic triad colors in this last idea even a wee bit, to a different shade or hue of tonic stability, we discover that at this upper, summit 13th level of our dominant arpeggio, our ability to subtly project our art towards either a major or minor key center can be easily realized. Example 3.

Transitions between our major and minor tonal centers. In surveying through our American songbook, we see that how we choose to weave our composition's story line through our major and minor colors is an exciting part of the compositional craft. In all of our styles, we can find this shifting between major and minor, and vice versa of course. Are we aurally portraying the two sides to each story? The call and response of human endeavor? The sense of hope of knowing that it's always darkest before the dawn?

So where is 13 in the music? In children's songs and folk music we'll surely see our Six colortone way more that Thirteen. But once we add a bit of the blue 7th / dominant spice, Thirteen becomes and essential color for many cats. So as the blues is simply core roots of Americana, so any style with a bit of the blues influence and we'll probably be able to also find the 13th color.

Similarly, 13 is a very common jazz color, so any style with a jazz influence would probably welcome this chordal coloring i.e., pop and various fusion musics. As we go through the following voicings for 13th chords we'll examine the musical styles too.

Theory properties / names. Turns out all three of our chord types unreservedly support the 13th. That the pitch is absolute organic and diatonic, and is also the relative minor position in the major diatonic scale surely wins the day. We label them as 13th chords mostly, meaning we've some sort of 7th below in our chord and the 6th is simply transposed up an octave to the 13th above in our voicings.

Tonic chord shapes / 13th. Examine the tonic functioning / 13 chord shapes in C major. Example 4.

Two chord / ii - minor shapes / 13th. Thinking along the lines of the Two chord / 13th chord shapes in C major, thus the D minor basis. Example 5.

Dominant / V 13 chord shapes. Thinking Two chord / 13 chord shapes in C major thus the D minor basis. Example 6.

Good mileage. These last eight root position shapes should give you pretty good mileage over the course. These next two chords are 'inversions', voiced with the 7th of the chord as our lowest pitch, we create a third inversion / V 13 chord. Same exact voicing, just two different shapes from two different strings. Rockabilly and jump love these two colors. Example 7.

That's trippy. Two different shapes exact same sound :)

Thirteen in action. Let's place the above shapes in spots we'd commonly find them in the music. Thinking musical style / context, the following ideas emerge.

Children's songs and Folk music. Probably 'hens teeth' to find these bigger shapes in these styles. The Six colortone is common of course, especially with songs in C major as the chord shape is accessible. Here is a Four / Five / One folk cadence ending up on C6, which really does sound a lot like A minor. Example 8.

The blues. Blues chords of course need a blue / dominant 7th to capture the magic. When we combine this with 13, we gain a solid functioning tonic structure chord that supports a number of different approaches of blue melodies, i.e., blues rock, country blues, jazz etc. This next bluesy V 13 voicing is very common. Here we use it as a constant structure to cover the principle One / Four / Five / One chords of our blues. Example 9.

Funk. Funk of course is a combination of rock and blues with a big 2 and 4 dance groove. Our 13th colortone plays a huge role as a sort of add on to our basic dominant 9th chord, which motors the bulk of the funk music of the 70's and onward. So we sound the the basic V9 chord then 'funk it up' with the added 13. Treble up your Strat and find a light pick :) "And dig that half step lead in ... " Example 10.

Bossa Nova. In this next idea we use a tonic function 13th chord to set up the core bossa guitar pulse. And while our 13th is built into the chord, we have the option of alternating our bass with a root / Five motion, so common to the bossa / Latin grooves adored by the dancers. Example 11.

video alternating bass

BeBop. In a bop direction ... as the general nature of bop is faster tempos, our chords oftentimes need to slim down a bit to gain the necessary sleekness for making the changes. One secret in sounding this sleekness lives in our picking / strumming hand. One approach with jazz guitar is the patented four finger / four string / four pitch school of modern guitar.

As the Two / Five / One motion is the core cadential of bebop, here are two 'lighter' turnarounds created with movable V13 chord voicings. The idea of light here implies that we use chord inversions thinking we'll let the bass player do the heavy lifting of harmony root motion. Example 12.

Sleeker yes? And a bit of quartile stacking to boot!

Straight Ahead. In what players term 'straight ahead' jazz, our voicings are oftentimes a combined root position chords or their inversions all with their 7th's and varied colortones. This next idea simply adds roots to the chords from our previous example. So of course the 'mix and match' process of these groups and really any other chords is in full force. Example 13.

Cool? A / B these last two back and forth to find the root pitches in the mix. Sing along if so inclined.

Minor modal fusion and beyond. We can find and use this next 13 chord voicing in many spots in jazz music, a bit in blues and pop too. It's a rather strong and sturdy chord and color, invoking a rather deep sense of minor, its longing and depth of heartfelt compassion. For emerging jazzers performing compositions such as Trane's "Impressions", this minor 13th voicing would be a potential first choice to learn and enjoy. Example 14.

Minor 13th chords / Dorian mode. Even from just the wee bit of music in this last idea, we gain a glimpse of the power of this minor 13 voicing and its strength in characterizing and capturing the emotional qualities of our Dorian mode. The Dorian grouping historically goes way back in our written records and was at the core of the modal jazz of the 1960's.

Review and beyond. The colortone we call Thirteen is at its core a major Six up from our root pitch then up an additional octave. While mostly a jazz color, the 13th finds its way into the blues and pop music. Loved by the rockabilly crowd, the V7 / 13 is the jump chord of choice.

Broad yet somewhat restive due to its perch atop our diatonic arpeggio, Thirteen sits and is the transition point between our major and minor tonal environments. As a minor tonic color, adding the Thirteen atop Seven or Nine brings forth the depth of our Dorian mode, that ancient grouping and color that lives in our DNA.

"It does not require many words to speak the truth."


(1) Isacoff, Stuart. Temperament ... The Idea That Solved Music's Greatest Riddle, p. 40-42. USA Alfred A. Knopf, New York. 2001

(1)Duffin, Ross W. How Equal Temperament Ruined Harmony, p.32. USA W.W.Norton and Company, NY, New York. 2007.
(2)Aebersold, Jamey and Slone, Ken. The Charlie Parker Omnibook. New York: Atlantic Music Corp., 1978.

Russell, George. The Lydian Chromatic Concept Of Tonal Organization. USA Concept Publishing Company, Cambridge, Mass. 1982