How to figure out any chord on the guitar.
The road map to chord structures. Part Three - Extended Chords, Poly-chords and Jazz Chords. [Advanced Intermediate Lesson]
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Thank-you, Dave.
Assuming you have read "Part One" and "Part Two" - this third lesson will be an introduction to extended chords, poly-chords and jazz chords. These types of chords can be rather intimidating for beginners and maybe even some intermediate guitar players. My hope is to alleviate some of the mystery about chords with bigger numbers and more symbols attached to them. Surprisingly enough, many of these chords are not "barre" chords.
Advanced Intermediate Lesson
What is an extended chord?
An extended chord is a four note chord, like a Major or dominant 7, with added notes on top of the chord. What are these added notes? Basically, I'm mostly going to look at adding variations on "9's", "11's" and "13's".
How can there be 13 notes in a chord?
That’s actually not how it works. Believe it or not, I get asked this question all the time from my students. When they see a chord that has a higher number like a 9, 11 or 13, they assume that there are that many notes in the chord. No. We only have six strings to play with. That means the most notes we can play for any chord on the guitar is six. Many jazz chords don't even use six strings. So, it becomes a "structured numbers" thing.
Where do these numbers come from?
Okay, now we must take a look at some basic music theory again, to understand the structures of chords.
Music uses the first seven letters of the alphabet, called "natural notes": A, B, C, D, E, F and G. (There is no "H"). If you look at a piano, these first seven letters are the white keys on that piano.
So, what notes are the "black keys"? This is where we change the names of those seven white notes, by adding symbols called "accidentals". These symbols alter the pitch of the natural notes, by raising or lowering their pitch.
For example, if the note "C" is raised one half step, it will be the black key located between notes "C" and "D", called a "C#" or a "Db" depending on which musical “key" we are in.
These “black” notes are called "enharmonic notes". However, for right now, we're not going to concern ourselves with the reasons why these notes are called enharmonic.
We are going to use these 12 notes for this lesson:
C - Db - D - Eb - E - F - F# - G - Ab - A - Bb - B
7 natural notes and 5 enharmonic notes gives us a total of 12 notes in music.
Each of these notes has its own Roman numerical position in music. This is what's called an "octave". An octave starts on one note (i.e. "C"), then counting the next 11 notes from "C" to "B". The note that would come after B would start the next octave at "C" again, starting the next octave higher.
Double Octaves
Okay so, now this is where we start to find where extended chords come from.
Imagine combining two octaves as one continuous line of notes:
C - Db - D - Eb - E - F - F# - G - Ab - A - Bb - B - C - Db - D - Eb - E - F - F# - G - Ab - A - Bb - B
How many notes is that? 24 notes. So, where do 9's, 11's and 13's come from if there are 24 notes?
Remember when I said that each of the notes has its own Roman numerical standing in music? Well, let's do that for this key of "C" major.
For the first octave in "C", we're going to get rid of the enharmonic notes and just leave the natural notes:
C - D - E - F - G - A - B
Let's give each note a Roman numeral:
C = I, D = II, E = III, F = IV, G = V, A = VI and B = VII
So far so good?
Now, if we double this, we're going to keep all of the "odd" numerals in both octaves, but we're going to change the names of the even number in the second octave, by adding "7" to the original numeral:
C = I, D = II, E = III, F = IV, G = V, A = VI, B = VII, C = I, D = IX, E = III, F = XI, G = V, A = XIII, B = VII.
Note, the D in the second octave has now become a "IX", the F has become an "XI" and the A has become a "XIII". All of the other notes have stayed the same.
Making a Major 9 chord
So, if I want to play a C Major 9 chord, I will need the following structure: I - III - V - VII and the IX. Those notes will be C, E, G, B and D. We might not actually use all five notes to make the chord. We might take the "G" (V) out of the chord, depending on how we decide to play the chord on the guitar.
Making a minor 9 chord.
We use the same approach to make a minor 9 chord, as we did building a Major 9 chord, however, we lower the “III” to a “iii” for the minor interval. Since this is not a Major 7 chord, it is a “dominant” 7 chord, we must also lower the “VII” to a “vii”
The structure now looks like this: I - iii - V - vii - IX.
The notes required to make a C minor 9 chord are: C, Eb, G, Bb and D.
I will continue on extended chord structures in Part Four. If you have any questions or comments, please feel free to do so below.