Duets naturally arrive at a conversational, kinetic charm that solo songs can’t. With Love Letter for Fire, Iron & Wine’s Sam Beam and singer-songwriter Jesca Hoop aim to channel the rapport of Kenny Rogers/Dolly Parton or George Jones/Tammy Wynette classics—where two singular voices merge in a dialogue that deepens the atmosphere. Each musician boasts a skill the other doesn’t—with Hoop’s vivacious, multi-hued sweetness brightening Beam’s smoky rumble and croon. Blending their voices in harmony, call-and-response and unison, they sing of love, spirituality and world-weary perseverance, often all at once. Their ace backing band, which includes Wilco percussionist Glenn Kotche and violinist/violist Eyvind Kang, flutters behind with minimalist arrangements drawing from traditional folk ballads, jazz, bluegrass and blues. “Midas Tongue” is a funky blues roller coaster, reminiscent of Iron & Wine’s “Woman King,” highlighted by brooding strings and Hoop’s heavy-breath percussion. “Know the Wild That Wants You” is an intricate vocal harmony showcase, with the singers pleading with each other to “heal your own heart.” Love Letter for Fire is built on this elegant give-and-take—it’s the rare A-list collaboration more compelling than the sum of its parts.