Curtis Salgado walks onstage, tells a room full of strangers he’s about to play some blues, some rhythm and blues, some funk and soul — “are you with us, music lovers?” — and within three songs the place belongs to him. Not because of volume. Because of a voice that can whisper a ballad into absolute silence and then blow the walls out on a deep-pocket funk groove thirty seconds later. Ninety minutes in, the audience feels like they went to church.