This week, the Philadelphia Orchestra premieres a new musical composition about its home city, by the city — in a way.

Boston composer Tod Machover has written “city symphonies” in Toronto, Perth, Detroit, and Edinburgh. Machover lands in a city, explores it through a tape recorder and hundreds of interviews with residents, and writes a large-scale work for orchestra.

He prefers places where he can weigh the good, the bad, and the ugly. Places populated by people who believe they live in a perfect city make him uncomfortable, he said.

“Here, I think you see all the sides of what’s possible, all the time,” Machover said. “It’s all mixed up. You can’t get away from it.”