Along with its companion, 5, 7 makes the case for Sault being one of the more interesting additions to the hip-hop conversation in 2019, an enigmatic soul-funk band whose pro-Black slant and deep, kaleidoscopic style make them sound as much like a missing link from the ’70s as a barometer of music and politics right now. Yes, they can party (“Over,” “Tip Toe”), they can protest (“Living in America”), they can go way out (“Waterfalls,” “Red Lights”). More importantly, they manage to make a project that feels communal and decentralized—the shifting vocalists, the shadowy roster of musicians—cohere into a single vision. How’s that for unity?