Scotty Moore fingerpicked some typical up-the-neck chords in "Milk Cow Blues." Elvis's version of this 12-bar blues is based on a 1930's recording by Tennessean Sleepy John Estes. Robert Johnson also recorded a version of the tune called "Milk Cow Calf Blues." Notice Moore's distinctive hammer-on figure played on a sixth-string-root A7 chord. It's the main lick in his backup played over and over.
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