Thriving between the hits, these finger-snapping gems prove that hard-and-fast genre boundaries meant nothing to Ray Charles. A sashaying live take of “Route 66” highlights his nimble piano style and husky vocals, while the bluesy 1956 single “Mary Ann” rides a frisky beat and swooning horns. And “X-Ray Blues” finds him sparring with Milt Jackson's tinkling vibraphone on a cool jazz number.