Donald Judd understood the power of emptiness. Though he hated being labeled a minimalist, the late sculptor (1928–94) was a master at finding visual power in simple forms and especially the negative space surrounding them. With his “stacks,” he created an iconic modern image by cantilevering book-thick squares from a wall and providing equidistant separation between them. This month, the first show devoted exclusively to those stacks is taking place on Manhattan’s Upper East Side at the same time that Judd’s former home and studio in SoHo has been opened to the public. Each of the 10 stacks imparts the energy of a deck of cards captured mid-shuffle. At Mnuchin Gallery, 45 E. 78th St., New York City, (212) 861-0020. Prices range from $5 million to $12 million.