He has wonderful, truly masculine vocals. It is difficult to describe Stevie, as difficult to describe as a good whiskey or favorite perfume fragrance with head notes of romance, "heart", created out of sadness, and subtle vicious loop. There are simply no suitable standards.
I like what Clapton said about SRV. "He was never lost". He lnew where he wanted to go at all times on his guitar. An all time great and favorite. Just saw Double Trouble and Jimmie Vaughan play at Antones. Really miss SRV. A guitar wizard.