Learn Maybelle Carter's Bass Note Technique
Since each note of a diatonic major scale belongs to more than one chord within a key, each note can serve as a bass note for several different chords in that key. Take a look at B, the third note of the G scale: itâ€™s the root of a Bm chord, but itâ€™s also the third of a G chord, and the fifth of an Em chord. Looking at bass notes this way gives you some flexibility to begin working melodic lines into the otherwise-basic chord progressions in the Carter Family repertoire. Example 7a shows a Gâ€“Dâ€“Gâ€“C progression in 3/4 time with root bass notes. This root-bass approach provides a sensible and reliable way to play the progression, but that doesnâ€™t necessarily mean you should stop there. Compare Example 7a to the ascending bass line in Example 7b. Here, weâ€™re playing an A bass note (the fifth) under the D chord and a B bass note (the third) for the second G chord.
Excerpted from Carter-Style Guitar Basics: Creating Basic Bass Melodies