“Can I get one with whiz, no onion?” a hungry young man called into the window of Pat’s King of Steaks. The counterman deftly spatulaed a sizzling skein of thinly sliced steak onto a roll and then applied a lacquer of Cheez Whiz to create a classic Phillly cheesesteak.

Taking it all in with a digital recorder and high-end binaural microphones one day in February was the composer Tod Machover, who writes symphonies about cities around the world and brings some of their most characteristic sounds into the concert hall.