Since we no longer get to experience real Rhythm and Blues music any more I'll highlight some artist who can "Sho'nuff Sang". I'm Starting with two artist who have amazing vocal range.
First there's Rachelle Farrell, who touts a 6 octive vocal range. If this means nothing to you, let me put it in perspective. There are 88 keys on a piano and she can sing 72 of them, she can sing Barry White and Minnie Ripleton notes.
Y'know what just check out this Live performant by her below. This was fairly recent too!
Next we have Will Downing. Another not so known singer but he has been at it for years and has a litany of albums as reference. He is most know for being able to sing any song in his baritone voice.
Here take a listen below. Will Downing singing wishing on a star(click for a better LIVE version).
and here is the two singing a duet.