“I’m singin’ to an empty chair,” Julia Steiner sings on “Just Want You to Know the Truth,” the eight-and-a-half-minute centerpiece of her band Ratboys ’ latest album, aptly titled “Singin’ to an Empty Chair.” It references a common therapy method in which a patient communicates with an open seat, and it serves as a sort of thesis statement for the project, whose songs touch on the difficulties of communication, and the often futile attempts to traverse the emotional and spatial distances that