Singer/songwriter Ashley Monroe’s fourth album begins with a heartbreaking gambit in slow waltz time: “How does a sparrow know more than I?/When its mother is gone/It learns how to fly.” Subtle, weatherworn, flecked with bits of disco (“Hard on a Heart”) and soul (“This Heaven”), Sparrow finds Monroe stepping away from the pop leanings of 2015’s The Blade, toward the gently orchestrated sound of artists like Lee Ann Womack, Alison Krauss, and Dusty Springfield, twisting traditions in careful but novel ways. Never a demonstrative instrument, Monroe’s voice keeps getting richer, too, hiding its rawest feeling in its most restrained moments, most notably the album-opening “Orphan.”