It is a clich to say that an orchestra is an example of the “whole being greater than the sum of its parts.” And it would be only a clich, if it weren’t so true. Each of 100 or so instruments plays a part that may sound obscure or just dull on its own. But all those parts come thrillingly to life when heard together in performance. Sara Fishko asked the New York Philharmonic to demonstrate some of their musical synergy.