Chord theory 3 - Added note chords
So far we have discussed:
- triads, constructed by stacking two thirds
- seventh chords, constructed by stacking three thirds
All additional chords can be grouped into the following two categories:
- extended chords
- added note chords
The most basic difference is that:
- added note chords DO NOT contain a 7th note
- extended chords ALWAYS contain a 7th note
Added note chords are a bit easier than extended chords, so we are going to look at them first.
Before we dive into added not chords, it helps to understand what extended chords are, because the main characteristic of added note chords, is that they are not extended chords. So we are going to start with a brief look what extended chords are.
Extended chords
Extended chords continue the concept of stacking thirds. After the 7th, this may include three additional notes:
- 9
- 11
- 13
The following diagram illustrates all of these notes in the key of C, starting the root C.
Some notes are more important than others.
The root and 7th are mandatory.
If you only play the root and the 7th, this would be called a shell chord or a shell voicing. This is something a pianist might play in the left hand.
The 3rd is the next most important note. The third identifies the chord as major or minor chord.
A chord with the root, 3rd and 7th is also called a shell chord or a shell voicing.
A shell chord simply means a chord where some notes - in particular the 5th - are missing.
Any chord which fits this general schema is either a 7th chord, or an extended chord.
Added note chords
Triads, 7th chords and extended chords all fit into the general concept of stacking thirds.
Chords which don't fit into that schema, are called added note chords.
We have already met one of these chords, which was the suspended 4th chord. The other important added note chords are:
- the 6th chord
- the add9 chord
- the 6/9 chord
Less important chords are:
- the sus2 chord
- the add2 chord
- the add4 chord
Terminology
When we talk about the notes in a scale, we often use names like third or fifth.
When it comes to extended chords and added note chords, it is common to just use numbers, like nine and eleven.
In English Grammar, these are called ordinal numbers (1st, 2nd, 3rd, ...) and cardinal numbers (1, 2, 3, ...).
Here are some common conventions:
Notes below an octave
Notes below an octave are usually referred to with ordinal numbers, like third, fifth and seventh.
Notes above an octave
Notes above an octave are usually referred to with cardinal numbers, like nine, eleven and thirteen.
Chord categories
When speaking about chord categories, we use ordinal numbers, like seventh chords or ninth chords.
Reading chord symbols
When reading chord symbols, we always use cardinal numbers, for example:
- C6 is spoken "C six"
- CΔ or CΔ7 is spoken "C major seven"
- C9 is spoken "C nine"
In altered chords - which we will meet later - a ♭ or ♯ symbol is spoken as "flat" or "sharp", for example:
- C7♭9 is spoken "C seven flat nine"
- C7♯11 is spoken "C seven sharp eleven"
- C9♭5 is spoken "C nine flat five"
Slash chords
There are in fact a few, let's say pesudo chords, which don't fit into the four categories listed above.
Before looking at them, we first have to get to know slash chords.
Slash chords are written in the format Chord symbol/Bass note, which means:
- play the specified chord (before the slash)
- play the specified bass note (after slash)
For example, if a chord is written as F/G, then it means "play an F chord, with the bass note G".
On the piano, it might look like this.
As you can see, this is an F major triad with a G as the bass note.
Let's look at how you might play an F chord and a F/G chord on the guitar.
Here are two ways to play an F chord. The first one is a barre chord using all 6 strings. The second one is a simpler version, using only the top four strings.
In both cases, the lowest note is F.
F/G
Theoretical
To change the barre chord into an F/G chord, we just have to move the bass note on the lowest string up two frets from an F to a G.
This way, we still have the notes F-A-C of the F major triad, but also G as the lowest note.
F/G
Practical
The F/G chord shown above would be difficult to play. By slightly changing the fingering, we can make another version of the chord which is easier to play.
This chord still has the notes F-A-C and still has G as the lowest note.
A slash chord is really just a form of notation and not really a new kind of chord. The slash chord notation is used in several different ways.
If the specified bass note is one of the notes in the chord, then it just an inversion.
For example C/G.
This is still a C chord, but by writing C/G we make it explicit, that you chould play an inversion with G as the base note.
In a lot of cases, a slash chord is just a different way to write a chord, which already has another name.
For example, the slash chord G/E
is identical to an Em7 chord.
Finally, there are some slash chords which cannot be described in any other way.
We have already seen one example above, with F/G. Another example is D/C.
Hybrid chords are what I described above as "pseudo chords". They are not chords in their own right, but have to be expressed as a combination of a chord and a bass note.
One common characteristic is that they are missing a 3rd note. In general, a chord must contain a 3rd note, which is
- a minor third
- a major third
- a suspended fourth as a substitute for the third
If we interpret the slash chord D/C as some kind of C chord, then it doesn't contain a 3rd note.
Added note chords
Now we are going to take a closer look at the following added note chords:
- 6th
- minor 6th
- add9
- 6/9
Sixth chord
In terms of chord factors, a sixth chord is made up of the notes:
- root
- major 3rd
- fifth
- sixth
That is the same as a major triad plus the sixth note.
When we discussed major triads, we showed that you can build a major triad on C, F and G using only the white notes on the piano. In all three cases, you can also build a sixth chord using only the white notes.
Here are those chords, illustrated on a piano keyboard.
C6
F6
G6
Movable guitar chords
As with the 7th chords, we are going to explore guitar chords by looking at movable chords, with the root on different strings.
In each case we will look at:
- a conceptual shape, with the notes in ascending order
- a playable shape, where the root is lowest note, but the other notes may be rearranged
So that we have enough space to the left, in particular for the conceptual shape, we will place the root on fret 7. This means the root will be:
- B on string 6 (the E-string)
- E on string 5 (the A-string)
- A on string 4 (the D-string)
B6
Root on string 6
Conceptual shape
Playable shapes
E6
Root on string 5
Conceptual shape
Playable shapes
A6
Root on string 4
Conceptual shape
Playable shape
Similarity to minor seventh chord
We have already looked at the minor seventh chord.
If we start making inversions on a C6 chord, we will find something interesting.
Root position
First inversion
Second inversion
Third inversion
Looking at the third inversion, you can see, that it is identical to the A minor seventh (Am7) chord.
We can see the same effect if we look at the guitar chords.
In both cases, the chords contain the notes C, E, G and A. The only slight difference is that the lowest note is a C or an A, but this doesn't singificantly change the sound of the chord.
In the C6 chord, we have effectively taken the sixth note, in this case A, and built a minor seventh chord on that note.
We can so exactly the same with any other sixth chord. For example, starting with G, the sixth note is E. This means that the chords G6 and Em7 contain the same notes.
Sixth chords as slash chords
Now we know that C6 and Am7 contain the same notes, we can explore some different ways to write them using slash chord notation.
| Slash chord | is equivalent to |
|---|---|
| C/A | Am7 |
| Am/C | C6 |
| Am7/C | C6 |
Sixth chords and thirteenth chords
In jazz music, you may have seen the chords C6 and also C13. C13 is a kind of extended chord which we are going to discuss later.
If we count through the notes in a C scale, we will spot something confusing.
The 6th note and the 13th note in the C scale are both the note A.
So what is the difference between a C6 chord and a C13 chord?
- The 6th chord never contains a 7th note.
- The 13th chord is an extended chord which always contains a 7th note.
Minor sixth chord
In terms of chord factors, a minor sixth chord is made up of the notes:
- root
- minor 3rd
- fifth
- sixth
That is the same as a minor triad plus the sixth note.
You can build a minor 6th chord on the root D using only the white notes on the piano.
Dm6
Movable guitar chords
Bm6
Root on string 6
Conceptual shape
Playable shapes
Em6
Root on string 5
Conceptual shape
Playable shapes
Am6
Root on string 4
Conceptual shape
Playable shape
Similarity to half diminished seventh chord
We have already looked at the half diminished seventh chord.
If we build the third inversion of the Dm6 chord, we can see that it contains the same notes as the Bø7 chord.
Dm6
Root position
Dm6
Third inversion
Bø7
Half diminished 7th
Bm7♭5
Minor 7th flat 5
We can see the same effect if we look at the guitar chords.
Dm6
Bø7
Bm7♭5
Both chords contain the same notes and have the same shape, but by adding a B as the lowest note it is changed from a m6 to a ø7 chord.
Add9 chord
In terms of chord factors, an add9 chord is made up of the notes:
- root
- major 3rd
- fifth
- ninth
That is the same as a major triad plus the ninth note.
Just like the sixth chord, you can also build a add9 chord on C, F and G using only the white notes on a piano.
Here are those chords, illustrated on a piano keyboard.
Cadd9
Fadd9
Gadd9
Movable guitar chords
Once again, we will look at movable chords in three versions, with the root on different strings.
Badd9
Root on string 6
Conceptual shape
Playable shape
Same as the conceptual shape
As an alternative, you can play the 5th note on string 2.
Eadd9
Root on string 5
Conceptual shape
Playable shape
Same as the conceptual shape
As an alternative, you could move the 5th up to string 1.
Aadd9
Root on string 4
Conceptual shape
Playable shape
Same as the conceptual shape
Add9 chords and ninth chords
The add9 and the ninth, for example Cadd9 and C9, are not the same.
This is basically as the difference between a C6 chord and a C13 chord, although the notation is inconsistent.
The difference is:
- The Add9 chord never contains a 7th note.
- The 9th chord is an extended chord which always contains a 7th note.
Add9 and add2 chords
The add9 and add2 contain exactly the name notes and are essentially the same chord.
This is what the Cadd9 and Cadd2 chords would look like on a piano, in their base positions.
Cadd9
Cadd2
In practice, the add2 chord symbol is hardly ever used.
Minor add 9 chord
In terms of chord factors, a minor add 9 chord is made up of the notes:
- root
- minor 3rd
- fifth
- ninth
That is the same as a minor triad plus the 9.
You can build a minor add 9 chord on the root D using only the white notes on the piano.
Dm(add9)
Movable guitar chords
Bm(add9)
Root on string 6
Conceptual shape
Playable shape
Same as the conceptual shape
As an alternative, you can play the 5th note on string 2.
Or this alternative
Em(add9)
Root on string 5
Conceptual shape
Playable shape
Same as the conceptual shape
As an alternative, you could move the 5th up to string 1.
Am(add9)
Root on string 4
Conceptual shape
Playable shape
Same as the conceptual shape
6/9 chord
In its basic form, a 6/9 chord is a major triad plus the 6 and the 9.
It contains the chord factors:
- root
- major 3rd
- fifth
- sixth
- ninth
It is very common to leave the fifth out and to play a 4-note chord with:
- root
- major 3rd
- sixth
- ninth
This would still be classed as a 6/9 chord.
This is how the two forms would be played on the piano.
C6/9
with 5th
C6/9
without 5th
Movable guitar chords
Once again, we will look at movable chords in three versions, with the root on different strings.
B6/9 with 5th
Root on string 6
Conceptual shape
Playable shape
In this version, the top four notes (3rd, 6th, 9th, 5th) are all separated by the interval of a fourth (5 semitones), which makes them easily playable on a guitar.
B6/9
Root on string 6
Conceptual shape
Playable shape
Same as the conceptual shape
E6/9 with 5th
Root on string 5
Conceptual shape
Playable shape
In this version, the top four notes (3rd, 6th, 9th, 5th) are all separated by the interval of a fourth (5 semitones), which makes them easily playable on a guitar.
E6/9
Root on string 5
Conceptual shape
Playable shape
Same as the conceptual shape
A6/9
Root on string 4
Conceptual shape
Playable shape
Same as the conceptual shape
Minor 6/9 chord
In its basic form, a minor 6/9 chord is a minor triad plus the 6 and the 9.
It contains the chord factors:
- root
- minor 3rd
- fifth
- sixth
- ninth
It is very common to leave the fifth out and to play a 4-note chord with:
- root
- minor 3rd
- sixth
- ninth
This would still be classed as a minor 6/9 chord.
This is how the two forms would be played on the piano.
Cm6/9
with 5th
Cm6/9
without 5th
Movable guitar chords
Once again, we will look at movable chords in three versions, with the root on different strings.
Bm6/9 with 5th
Root on string 6
Conceptual shape
Playable shape
Bm6/9
Root on string 6
Conceptual shape
Playable shape
Same as the conceptual shape
Em6/9 with 5th
Root on string 5
Conceptual shape
Playable shape
Em6/9
Root on string 5
Conceptual shape
Playable shape
Same as the conceptual shape
Am6/9
Root on string 4
Conceptual shape
Playable shape
Same as the conceptual shape