The hall has shrunk and become warmer, more intimate. The audience now surrounds the stage, with some seats close enough to hear wind players breathe between phrases and watch beads of sweat form on the conductor’s brow. Banished from the lobby, the DMV-style ticket booths have been replaced by a hangout zone with a 50-foot-wide digital screen that will broadcast concerts live and free to anyone who cares to stop by. A garage door opens onto the plaza. A new Afro-Caribbean restaurant plans to put bodega-style chopped cheese sandwiches and braised oxtails on the menu.