Welcome to the third lesson of the Blues Guitar Quick-Start Series. The focus of this lesson will be dominant seventh chords. These are some of the most commonly used chord shapes in blues music. We’ll start by learning the basic shapes, then move onto applying them to the 12-bar blues progression.
Dominant seventh chords contribute a lot to the overall sound of blues music. A dominant seventh chord is made by taking a major chord and adding a lowered 7th scale degree to it. You don’t need to focus on exactly what that means right away. It’s more important to just understand why we use these chords and get the basics of the chord shapes down first.
Typically, a dominant seventh chord would only be used for the 5 chord. But when you’re playing the blues, you can use it on every chord in the 12-bar blues progression - the 1, 4, and 5 chords. This is because of the fact that blues music is a hybrid of major and minor tonalities.
These new chord shapes are pretty easy to get the hang of with the exception of the B7. This is because we’ll need to use a B major bar chord shape to play it. With the E7 and A7 shape you can simply remove your finger from one of the strings, and the open string takes care of the added lowered 7th. With the B major chord, you’ll play the same shape as the A7 chord, but with a bar on the second fret.
Focus on learning each one of these shapes independent of one another at first. Once you’ve got the hang of each chord on its own, you can work on changing between them. Start off slowly, and when you’re ready you can practice apply these new shapes to the 12-bar blues progression you learned in the last video lesson.
There are a few other dominant seventh chord shapes you can learn as well. However, we won’t be using them for the musical application portion of this lesson series. They’ll be used in other keys you may encounter when playing the blues. To learn these shapes you’ll want to reference the video portion of this lesson.
In the next video, we’ll start approaching the blues from a different angle. Instead of using power chords or dominant seventh chords, we’re going to learn how to incorporate a basic blues riff that you can use to play through a standard 12-bar blues progression.