Welcome to the latest installment of Chord by Chord, a series designed to build your understanding of harmony and the fretboard. Last time I showed you how to create different D7 voicings from D major chords. This time I’ll demonstrate the same with G7 and G.
As a refresher, a G major triad is comprised of three notes—the root (G), major third (B), and fifth (D), as shown in Example 1. To get a G7 chord, all you have to do is add a flatted seventh, which in this case is F natural (Example 2). Remember, you’re lowering the seventh, F#, by a half step.
Example 3 shows a G7 voicing derived from an open G shape. The easiest way to switch between G and G7—which is actually something that you often have to do in popular music—is to keep your first finger on the F on string 1 for both chords; for the G major chord, fret the G on string 1 with your fourth finger. Then, to get to the G7 chord, all you have to do is lift your fourth finger. You can also try muting the fifth string in both of these open chords, for a tighter sound.
The next two examples are based on barre chords in third position. For Example 4a, all you have to do is lift your fourth finger from the G chord to get to G7, similar to what you did in Ex. 3. In Example 4b, you’re basically playing the same G7 shape, but doubling the flatted seventh with your fourth finger on string 2, fret 6. When playing these examples, remember that you don’t have to play all six strings; for example, experiment with sounding only the bottom or top four strings.
Example 5 gives you nice, clean voicings played on the top three strings. As the G7 in Ex. 5 omits the root note (G), it works especially well when you’re playing with a bassist or pianist. Now check out some barre chords in tenth position (Example 6), which can be tricky to play, depending on your guitar. Remember that you don’t need to include all five notes in each voicing.
You should now know how to construct a G7 chord and how to transform various G major shapes to G7. A great song that makes use of your new chord is Johnny Cash’s “I Walk the Line.” Next time we’ll continue exploring the dominant seventh chord, through a range of C and C7 voicings.