Chord Construction Part 8: The Extended Dominant Chord

The Theory:

For this explanation we are going to start with a 7th (Dominant 7) chord as our foundation or starting point.

As you know a 7th (or 7, or dom7) chord contains these Intervals:

R M3 5 b7

With C as the root a C7 would have these notes:

C E G Bb

This is a concept you must grasp to continue on, as it will make it very easy to see things transform as we continue.

Let's look at every other note in a two octave Major Scale but with the b7 replacing the M7:

R M3 5 b7 9 11 13

This will be the group of notes we will use to build the a chord past a dom7 chord. Just a side note, these are also the Intervals of a Mixolydian scale.

To continue building Extended Dominant Chord formulas, use the dom7 formula and "stack" the remaining notes on top of it.

When you stack the remaining notes on each other you keep extending the chord to a bigger chord.

These are the chord names and chord formulas you create:

7 = R M3 5 b7
9 = R M3 5 b7 9
11 = R M3 5 b7 9 11
13 = R M3 5 b7 9 11 13

See how we keep stacking the notes on top of each other including all notes before the highest Interval? This is the key idea behind Extended Chords...you keep extending it higher and higher.

So,

in order to call a chord a 9 chord, it has to have a R M3 5 b7 and 9.

in order to call a chord a 11 chord, it has to have a R M3 5 b7 9 and 11.

in order to call a chord a 13 chord, it has to have a R M3 5 b7 9 11 and 13.

With these "rules" we can think of the Extended chords as being "inclusive chords". Meaning, to go any higher in number we need to include the Intervals/3rd's below it.

They are also inclusive when you notice the highest Extended Dominant chord you can build, a 13, includes every note name in the scale listed above (the Mixolydian scale).

Here's an example with the notes, in order, for a C13:

C13 = C E G Bb D F A C

Re-order those notes and you get:

C D E F G A Bb C... These are all the notes in a C Mixolydian Scale.

Ok...that's the "theory" behind it...the "reality" behind it is where things can get tricky and blurry. But, if you use all the Chord building formulas/ideas that I've shown in this series, things become "logical" when trying to figure out what notes make up what chord.

The Reality:

With the lay out of the guitar you are probably already aware that sometimes you "double" notes or "omit" notes when playing chords. This is commonly apparent when looking at the guitar like: five fingers and six strings. You can see where you might have to omit a note or double a note sometimes.

Also, if you look at the dom13 chord, it has seven notes in it...and we only have six strings. So, you can see where some notes going to have to be omitted.

What if you where asked to play a C13 chord...one of the few (not the only) ways you can play ALMOST EVERY note in the chord is like this:

--10- = 9
--10- = 13
--9-- = M3
--8-- = b7
--8-- = 11
--8-- = R

Remember, the dom13 chord is a seven note chord, so with six strings we are going have to omit some note. In this chord we've omitted the 5. If you remember the 5 wasn't detrimental to a chord/Triad being Major or Minor...it was the M3 or the b3 the MADE a chord Major or Minor.

So, it is very common to start omitting notes by looking at the 5 as a possible note to drop.

But, now that we've removed the 5, can we still call this chord a C13 chord? With a note omitted, it is not completely inclusive anymore, or completely stacked.

Yes, you can still call this chord a C13, and you can still use this chord as a C13 chord.

So now what???

You will find that one of the biggest/common clashes you will run into with Extended Dominant Chords is when the 11 Interval is either next to a M3 or it replaces a M3.

This 11 against the M3 "rub" is the same rub we had with the Extended Major Chords, if you remember.

Although, the rub isn't as bad with the Extended Dominant chord, you should still watch out for it. Having the M3 and 11 in the chord gives it a dissonant "rub". And, it's not what we want to hear when playing a Dominant type chord. Dominant chords are bluesy and friendly, right?

If you did omit the M3, the 11 sounds like it replaces the M3...remembering the 11 can also be called the 4 (4/11) and remembering the theory behind a Suspended Chord...having an 11 and no M3 could give the chord a sound of a sus4 chord. Like the 11, or 4, leaves it hanging, unresolved. Like "where's the 3rd?"

So, another note you may want to try as a possible note to omit is the 11 when playing a dom13 chord.

All the other notes, R M3 5 b7 9 and 13 should sound fine together most all the time and in any given order. Still, just pay attention to the 11, ok?

So, with these two "rules" or common practices, let's revise the chord I presented and hear the killer sound of a C13 on the guitar:

--10- = 9
--10- = 13
--9-- = M3
--8-- = b7
--x--
--8-- = R

Now doesn't that sound much better? To most people it will. By using those two common practices for Extended Dominant chords you end up with a very nice sounding C13 chord, containing a good amount of the needed notes too.

Ok, in reality now that we've dropped the 11, we could add back in the 5 if we wanted:

--10- = 9
--10- = 13
--9-- = M3
--8-- = b7
--10- = 5
--8-- = R

But, that's not too practical to play on the fly. So let's stay with this chord as one possible way to play a C13 chord:

--10- = 9
--10- = 13
--9-- = M3
--8-- = b7
--x--
--8-- = R

Let's look at some other realities with naming Dominant Extended chords, and keeping in mind all the other chord formulas we worked with in the past lessons.

In a dom9 chord (R M3 5 b7 9) what if I needed to omit the b7 note due to the voicing that worked best for a chord. This leaves me with:

R M3 5 + 9

Isn't that also the formula for a "add9 chord"? But, it could also be thought of as a dom9 chord with b7 omitted.

These are the kind of "gray areas" you can run into with chords. The more you know about formulas the easier it is to adjust and "have a chord to play" for what might be charted out on a sheet of music.

If the sheet music was to decide for you that you must omit the b7 interval, they would've named it an add9 chord. But, in functioning on the guitar and finding voices, the dom9 chord could be played as an add9 chord and no one will yell at you.

More reality...

If it calls for a dom9 chord and you play the one with the b7 omitted, are you wrong? Not really in reality. The determining factor is, how does it sound? If it sounds like it covers the "needed" notes to make things flow, then go ahead and play it. If it sounds like it's missing something, try omitting a different Interval and adding back in the b7.

Now you can see the more you become familiar with chord formulas the more flexible you can be and still cover the basis, or "have a chord to play".

A comparison...

Let's compare the maj7, m7, and the dom7 chord formulas to see a common point of view that a lot of musicians are aware of:

maj7 = R M3 5 M7
m7 = R b3 5 b7
dom7 = R M3 5 b7

You can see between the maj7 and m7 that both the 3 and 7 are flatted in the m7 chord. We'll with the dom7 chord people think of it as primarily a Major Triad with a b7 added. So, this makes the dom7 chord pretty much a Major chord. But, once we start extending it, it starts to take on traits of the Extended Minor chords. Hopefully you can grasp that.

Now let's look at the Extended 13 formulas:

maj13 = R M3 5 M7 9 11 13
m13 = R b3 5 b7 9 11 13
dom13 = R M3 5 b7 9 11 13

Let's think of playing a dom13 chord (R M3 5 b7 9 11 13). While omitting notes from the formula so we can play them on the guitar look what can happen:

1. if the note we omit from a dom13 is the M3, this chord looks and could function as a m13. Both chords, without a 3 would have R 5 b7 9 11 13, right?

2. if the note we omit from a dom13 is the b7, this chord looks and could function as a maj13. Both chords, without a 7 would have R M3 5 9 11 13, right?

It's important to realize that the Dominant chord has a little bit of sound from both the Major and Minor chords. Kind of like "the best of both worlds". This is a fundamental understanding most musicians see as a common way of thinking about Dominant chords. It also pays off when playing scales over the Dominant chords. And, you'll find as your studies continue, that the Dominant chord ends up being one of the most interesting chords we have and can tie into many different areas...the Major/Minor thing is just the beginning.

Without getting too hog-wild or contorted, here's a number of movable Extended Dominant chord forms (Remember whatever note name the Root is, is also the Root of the chord or the note name of the chord). Every chord may not contain every stacked note, or some may sound better than others, but it should give a good foundation for finding where Intervals are located on the fretboard from the Root note, and playing some of these common chords. (You'll notice that the ones without the M3 are actually the same fingering as some of the Minor chords in the last lesson)

C7:

--x--
--5-- = M3
--3-- = b7
--x-- =
--3-- = R
--x--

--3-- = 5
--5-- = M3
--3-- = b7
--5-- = 5
--3-- = R
--x--

--x--
--8-- = 5
--9-- = M3
--8-- = b7
--x--
--8-- = R

--x--
--x--
--9-- = M3
--8-- = b7
--x--
--8-- = R

--x--
--8-- = 5
--9-- = M3
--8-- = b7
--x--
--x--

--x--
--11- = b7
--9-- = M3
--10- = R
--x--
--x--

--12-- = M3
--11-- = b7
--12-- = 5
--10-- = R
--x---
--x---

C9:

--3-- = 5
--3-- = 9
--3-- = b7
--2-- = M3
--3-- = R
--x--

--x--
--3-- = 9
--3-- = b7
--2-- = M3
--3-- = R
--x--

--x--
--8-- = 5
--7-- = 9
--8-- = b7
--x--
--8-- = R

--x--
--8-- = 5
--7-- = 9
--8-- = b7
--7-- = M3
--8-- = R

--x--
--8-- = 5
--7-- = 9
--8-- = b7
--7-- = M3
--x--

--10-- = 9
--8--- = 5
--9--- = M3
--8--- = b7
--x---
--x---

--10-- = 9
--11-- = b7
--9-- = M3
--10-- = R
--x----
--x---

C11:

--3-- = 5
--3-- = 9
--3-- = b7
--3-- = 11
--3-- = R
--x--

--x--
--6-- = 11
--9-- = M3
--8-- = b7
--x--
--8-- = R

C13:

--10- = 9
--10- = 13
--9-- = M3
--8-- = b7
--8-- = 11
--8-- = R

--10- = 9
--10- = 13
--9-- = M3
--8-- = b7
--x--
--8-- = R

--x---
--3-- = 9
--2-- = 13
--2-- = M3
--3-- = R
--x---