This guitar part is built around a B minor to A major chord change, with interesting twists and turns along the way. The first chord forms a ringing melody established by picking individual notes on the first, second and third strings. Maintain pressure on each fretted note, so they ring over each other. For contrast, Auerbach ends every other bar with an abrupt chord stab. This locks in effectively with the drum groove, and adds an element of surprise to the relaxed feel. The warm tone is achieved by using the fleshy part of your thumb to gently strum downstrokes.
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