I like the blues - Chicago, Delta or Jump Blues which provided a big part of the foundation of rock & roll.

Since it's Billy Ward's birthday, here you go: https://www.youtube.com/watch?v=OpQuNY3XFI0

Another dude is blues shouter Big Joe Turner:
https://www.youtube.com/watch?v=MJsod7Lgn8E

Or Big Mamma Thorton singing a tune Elvis covered:
https://www.youtube.com/watch?v=yoHDrzw-RPg

I wonder where it would have gone if Elvis, Pat Boone & the other 'acceptable' singers hadn't been pushed forward in place of the real musicians creating a new musical genre'.