Three blue guitars mark the spot where Delta blues henchman Robert Johnson is said to have sold his soul to the devil in exchange for mastery of the guitar.

BBC: Music City to Dixieland: A musical roots run

And with help from West, Blue Collar is full of big, hooky beats with soul samples and rippling guitars, as well as some less typical hip-hop fair.

NPR: 'Blue Collar': Rhymefest on the Way Up