The Complete Sessions in which Louis Armstrong sings, scats, and blows Duke Ellington’s tunes and accompanied by the composer himself on the piano, what more could the jazz aficionados ask for? In “I Got It Bad and That Ain’t Good,” Satchmo demonstrates his mastery as a distinctive singer as well as an unmistakable trumpeter. Pops’ solo, which complemented by Duke’s minimal piano, is so damn fine and mellow. Even though Duke is an extraordinary pianist, he only plays when necessary, and when he does, the result is spellbinding. “I’m Just a Lucky So and So” is a perfect example. The way he plays the blues with his stride technique (pay attention to how he grabs notes the intro) and the way he plays behind Satchmo’s vocals are inimitable. Big up Pops and Duke!