“Philadelphians sometimes need reminding by outsiders: Though they’re used to having the world’s largest pipe organ in the downtown Macy’s department store, virtually no similar establishment, possibly worldwide, has everyday organ concerts from Bach to Broadway raining down from the women’s lingerie department.” On Saturday, the Philadelphia Orchestra will give a concert with the store’s Wanamaker organ for “roughly 1,200 listeners seated on the main floor and two successive tiers – and paying $100 to $5,000 a ticket.”