Chord Extensions With 4-Note 7th Chord Voicings PART 1

This is a bit more of an advanced tutorial in dealing with seventh chords and their relative extensions. For this tutorial, you will need a little bit of an understanding of diatonic seventh chords, their complementary scale/mode, and the extensions available for each chord type.

Take a look below at Figure 1. This shows a G major scale starting on the note "C' which is also known as the C Lydian mode of the G major scale. It's relative seventh chord, Cmaj7, is highlighted below by identifying each primary chord tone (Root, Major 3rd, Perfect 5th, and Major 7th) within the scale.

The chord tones on the staff are C, E, G, B. Notice how the primary chord tones go up the scale in intervals of 3rds or every other scale tone. Now, notice how there are 3 notes left over in the scale that are not identified as primary chord tones for Cmaj7. The notes D(major 2nd), F#(augmented 4th), and A(major 6th) in the scale.




Now lets look at Figure 2 and see this another way. Our leftover notes in the scale from Figure 1 are going to become our chord extensions. In Figure 2, we will stretch the scale up 2 octaves. By continuing to stack the scale notes in intervals of 3rds, past the 7th degree, and above the octave C, the leftover notes become our chord extensions: D, (major 2nd) becomes the major 9th. F# (augmented 4th), becomes augmented 11th. A (major 6th), becomes the major 13th.

Now, we can take these tones and stack them in 3rds and play them as harmony, we will get the chord Cmaj13(#11) in Figure 3. 

The Meat:
So there is a basic crash course in chord extensions. Now, how do we play all this stuff on a guitar. For the rest of this chapter, we are going to break our Cmaj13(#11) down to just a 4-note chord by substituting some of our primary chord tones (roots and 5ths) with the extension notes. In most cases, this is the only way that we can play some of these chords on the guitar because of the limited amount of tones that we can play at the same time. These voicings are most effective in the presence of bass instrument which is primarily playing the roots of the chords in the bottom part of the collective harmony. Since our new chord voicings will be excluding the root of the chord, it will be important to hear it elsewhere as we work through each example. I would recommend using a loop pedal or other recording device that can play the low root note of the chord as you play through these. Play a C root note on the 3rd fret/5th string and record it and that will work fine.


Let's get started with Ex.1 below. Look at the first voicing, Cmaj7, and learn it on your guitar. Learn where the root, 3rd, 5th, and 7th functions are within the voicing. After you familiarize yourself with this chord structure, take a look at Cmaj9 just to the right of it. All of the other notes of the Cmaj7 structure before it are still there except for the root note which has been replaced by a tone that is one scale tone (whole step) above it on the same string. This is called a 9-for-1 substitution.

Let's take a look at Ex.2 and add another substitution. In addition to the 9-for-1 substitution, we will add the 11-for-5 which is moving the 5th down a only a half step because it is an augmented 11th. Because the 11th is altered, it is denoted in parentheses as #11 as a clear way of communication. The chord is written Cmaj9(#11).

In Ex.3, We will still use the 9-for-1 substitution that we used in the previous two examples and we will also add the 13-for-5 which substitutes the 13th for the 5th of the chord. The note G (5th) slides up a whole step to A which is the 13th. Play this chord over your low C bass note as you have with the others. Try it in a chord progression.

Ex.4 is going to give us the 9-for-1 and the 13-for-5 as we saw in the last one but we are also going to include the #11th extension as well. Since the 5th function is already spoken for in the 13-for-5, we are going to take the 3rd (E) and substitute the #11th (F#) for it, giving us what's called 11-for-3. You know what to do!

Afterthought: These are just a few examples of how you can take one 4-note seventh chord voicing and substitute primary chord tones for chord extensions. You can use this same process to add extended harmony to different seventh chord types. Try lowering the 7th a half step to make the chord C7 and use the same process to create extended harmony. Remember, not every extension is agreeable with every chord type. Extensions can either be derived from the respective chord/scale relationship OR can be altered to create more interesting tensions or colors in the harmony.

There will be more on this later. Enjoy.