7. Billie Holiday

The voice that launched a million X Factor hopefuls. Wonderful, of course. Her later material when she sounded wounded and wretched is just as beautiful to me, but this is the era we played at Barrelhouse, the classic dance music. It says something about the quality of a singer that one can still hear her influence on new singers all these years on, even if the new singers are maybe blissfully unaware of her, having inherited their stylings through Amy Winehouse and such.