It takes two to tango, but imagine what nine can do, in a program that culminates with Argentine composer Osvaldo Golijov’s high octane nonet, Last Round. The Brooklyn-based Knights, “spirited and vital” (New York Times), lead us on a tango tour, which follows the world’s most romantic dance around the globe, as it inspires composers from Ravel to Stravinsky to the great tango nuevo master Astor Piazzolla.