In this new, 5 part series we’ll be looking at the importance of the dominant 7th chord and some of the more unusual places that you can use them. In part 4, we’ll be looking at how to use dominant 7th on chord 3:
So far in this series, we’ve been looking at the dominant 7th chord in its most familiar context, part of the perfect cadence (V – I). Over the weeks, we’ve been putting dominant 7th chords in more unexpected places, creating perfect cadences in other parts of the key. This week we are going to be focusing on chord 3.
Chord 3 in a major key is a minor chord, so in order to change it into a dominant 7th we will need to raise the minor 3rd up to a major 3rd and then put a flat 7th on top. Like chord 2, which we looked at last week (and is also usually a minor chord), this changes the sound more drastically than when we change chords like 1 and 5, which are already major chords. Let’s look at what I mean:
We’re in the key of C:
I ii iii IV V vi vii
C Dm Em F G Am Bº
Chord 3 is E minor and its notes are:
1 3 5
E G B
The original triad (notes 1, 3 and 5) make up the basic foundation of the chord. So, in order to change it into a dominant 7th chord, we will have to alter the original triad by making the minor 3rd a major 3rd instead.
1 3 5 7
E minor 7: E G B D
1 3 5 7
E dominant 7 (E7): E G# B D
If we treat chord 3 as a temporary chord V and complete a perfect cadence then it will take us to the relative minor of C major (or the relative minor of whatever key you’re in):
Temporary function: (V – I)
Actual function in C major: III vi
As we know, every major key has a minor key that shares a lot of similarities with it; these are called ‘relative minors’ or ‘relative majors’ depending on where you are coming from. So, in its simplest form, the reason we can use a dominant 7th on chord 3 is because it is the dominant/chord V of the relative minor.
Using a dominant 7th on chord 3 in a functional way (resolving to the relative minor) can create a really nice Gospel/soul/funk sound. Check out the chorus from ‘Virtual Insanity’ by Jamiroquai:
IV III vi II
Cb∆ Bb7 Ebm7 Ab7 (∆ means major 7/can extend to major 9 too)
Note: Cb∆ is the same a a B∆. The reason you’d say C∆ rather than B is because the next chord is a Bb. You wouldn’t have a B and a Bb chord (or F and an F# chord etc.) in the same key.
Also: See that Jamiroquai is using a secondary dominant when playing the Ab7.
Let’s look at a few ways that people have used this technique in a non functional way.
As we looked at earlier on, the dominant 7th changes the nature of chord 3 from a minor chord to a major chord. Here are a couple of examples of artists that have taken advantage of this idea, forgetting the 7th and simply using it as a major chord:
The Suburbs by Arcade Fire:
I vi III V
D Bm F# A
Creep by Radiohead:
I III IV iv
G B C Cm
Notice that in both songs, the chord sequence is used extensively, without feeling the need to hurry on to other progressions to keep the song interesting. This seems to be coming up again and again as we look at different techniques. Good songwriting isn’t always about making everything more complicated, but can often be about making the most of the few chords that you do choose to use.