and for bonus points, Lewis Rawls singing backup to Sam Cooke on Bring It On Home To Me.

for Soul.

For blues I'd say Muddy Waters

It was wonderful

But heard a nice one titled Hands of Time. Is the group named Collateral?

Hands of Time played in the film with Tom Cruise and Jamie Foxx. Still don't know the musician.

Trying to post a YouTube link here:

When I was a head bangin' teen rocker I was too cool for that soul music, but after some years I realized what I was missing. I will always reach for the volume knob when when I hear the intro to "Let's Get it On".

I didn't know Led Zeppelin, Cream and The Rolling Stones were playing the blues either. Amazing what you learn when you aren't cool anymore.

Hell, Willie Dixon wrote Cream's big hit "Spoonful" and Zep's "Whole Lotta Love". Skip James wrote "I'm So Glad", and I won't even start with The Rolling Stones catalogue.

Those bands wrapped those songs up in psychedelic gift wrap and sold them to a young me as hard rock that was supposed to freak out my parents.
I should sue.

The songs were written by Blue singers.

Sonny Boy Williamson, Magic Slim & The Teardrops, Son House, Charley Patton, Skip James, Johnny Shines, Robert Johnson, Albert King... I could go on.

along with Billy Preston and The Temptations.

That's the music I grew up with.

Lightnin' Hopkins is a long time favorite.
Contemporary favorite artists Corey Harris, Sam Fish and Carl Bundt (Daddy Stovepipe on the YouTube).