He smiles a lot onstage, but wow, does Buddy Guy know how to make a guitar cry, especially when he busts forth with the signature technique shown here. Perfect for a soul-searching slow blues in D minor—the most tear-jerking of all keys (at least according to Spinal Tap)—this fingerplucking approach (which ZZ Top’s Billy Gibbons uses as well) finds Guy sounding a bitterly sad pentatonic lick on the middlemost strings while an upper-octave first-string root (D) chimes sweetly throughout. Bittersweet.