Rhiannon Giddens and Francesco Turrisi share conservatory beginnings and a boundless musical curiosity. In Weill Recital Hall, they reinvent the voice-and-piano recital with an eye to tearing down the artificial boundaries between classical and vernacular music. Drawing on diverse sources—such as American and Italian folk music, early Baroque songs, classical arrangements of African American spirituals, original songs, and deconstructed opera arias—they show the fluidity between the classical and popular sound.