Philadelphia’s Kimmel Center for the Performing Arts will finally be complete this week, when the center unveils a massive $6.4 million, 32-ton, 6,938-pipe organ in its main concert hall, and inaugurates it with a 10-day festival featuring the Philadelphia Orchestra. “The specs alone make you want to hear what will be the largest functioning concert-hall organ in the United States. The Kimmel instrument – in contrast to the sensible but disappointing portable organ once used in the Academy of Music – is the magnum opus, eight years in the making, of the busy Dobson Pipe Organ Builders Ltd., of Lake City, Iowa.”