The expression of feeling and emotion in music is not necessarily the same as vocal quality or range. From the listener's viewpoint, it is a very subjective thing.

Here's a starter of singers who move me because they convey the emotions of a song. Other than that, you'd be hard-pressed to put them in the same category:

   Ray Charles for shear strength of soul and exuberance
   John Lennon for raw emtion and sensitivity (a rare combination)
   George Jones and Lyle Lovett
   Michael Stipe of R.E.M.
   
   and some singers who don't have what is usually considered a "good"
   voice:

   Tom Waits
   Louis Armstrong
   Jimmie Durante

I'm sorry, Little Hawk. William Shatner didn't make the cut.

Who would you add?

Jerry