Who Else Is Interested In Learning The Classes Of Extended Chords

In today’s lesson, we’ll be looking at the classes of extended chords.

It’s important for any serious musician to learn about extended chords because they are harmonically ahead of other chord classes like triads and seventh chords.

Having covered extended chords in a previous lesson, let’s go ahead and explore the three classes of extended chords.

A Quick Review On Extended Chords

Preliminaries

According to Jermaine Griggs, “a chord is basically a collection of three or more related notes (agreeable or not), which may be played or heard together.”

It takes at least three notes to form a chord, and the notes of the chord must be related to a given scale (scale relationship) and interval (intervallic relationship.)

In the C major triad:

…the notes C, E, and G, are related to the C natural major scale (scale relationship):

…and third intervals (intervallic relationship):

This explains why C to E:

…and E to G:

…are third intervals.

“What Is An Extended Chord?”

A chord can be classified as an extended chord if its width exceeds the compass of an octave.

Using the note C (as a reference):

We’ll have C to C:

…as an octave.

All chords with this C note (as their root):

…that exceed the compass of its octave (C to C):

…are classified as extended chords because their width are literally extending beyond the compass of an octave.

The Formation Of Extended Chords

Pursuant to traditional chord formation guidelines, anyone can form chords in third intervals (intervallic relationship) using a given scale.

Using the C natural major scale:

…a chord can be formed in third intervals – from C:

…to a third above C (which is E):

…to a third above C-E (which is G):

At this point, we’ve formed the C major triad:

Adding another third to C-E-G:

…(which is B):

…produces the C major seventh chord:

Adding another third to C-E-G-B:

…(which is D):

…produces an extended chord – the C major ninth chord:

Adding another third to C-E-G-B-D:

…(which is F):

…produces an extended chord – the C major eleventh chord:

Adding another third to C-E-G-B-D-F:

…(which is A):

…produces an extended chord – the C major thirteenth chord:

“In A Nutshell…”

Beyond the level of seventh chords are extended chords. This means that adding a note to a seventh chord, that is a third above it, produces an extended chord.

There are three distinct classes of extended chords and that’s our focus in this lesson. Join me in the next segment so we can discuss elaborately on it.

The Classes Of Extended Chords – Explained

All extended chords belong to one of these three classes:

Ninth chords

Eleventh chords

Thirteenth chords

Take a closer look at these chord classes.

Ninth Chords

Ninth chords are extended chords that encompass a ninth interval from their root.

In the key of C major:

…a ninth chord should encompass C to D:

…a ninth interval.

Beyond the size of a ninth chord, it’s important to also take a look at its chord tones which are:

The root

The third

The fifth

The seventh

The ninth

A ninth chord consists of five chord tones and can also be considered as a seventh chord with a ninth tone.

There are various ninth chord qualities which include (but isn’t limited to):

The major ninth chord

The minor ninth chord

The dominant ninth chord

The minor-major ninth chord

The diminished major ninth

Final Words

There are basically three classes of extended chords:

• Ninth chords
• Eleventh chords
• Thirteenth chords

…of various qualities – major, minor, dominant, etc., and we’ll explore them in subsequent lessons.

Thank you for your time.