“Can an orchestra belong to a city?,” Esa-Pekka Salonen wonders in voice-over. “Can an orchestra capture the spirit of its city? And at the same time, can it make boundaries disappear? The answer lies in open-mindedness and curiosity, because music connects us in a way nothing else does.” As musical institutions everywhere—as humanity itself—crosses new thresholds, this hour-long program, originally televised in November, takes tentative steps forward. The premiere of Nico Muhly’s Throughline, a chamber-music mosaic performed on a symphony stage, begins to propose answers to Salonen’s questions.—M.G.