Reinventing vocals, timing ... the whole of music. Armstrong recorded this in 1931 - imagine the excitement and pure joy this utterly new and brilliant form of music had on an America bursting at the seams. The tune begins typically, saxes come in real hokey, corny, playing the melody. And then ..... in comes Louis, condescending, saying uh huh, sure, all right, to their very conventional, old-fashioned way of playing Up a Lazy River, and in he comes showing them a whole new way of playing melody. Completely free -- the music boiled down to its essential oils. Boiled down to one note -- and then he improvs. Wow. He invented swing. He transformed American music forever.
Clearly, Armstrong is the most influential vocalist that America ever produced. And don't get me started on his horn.