This was a really cool day at my Church First Congregational (UCC) in Riverside - I got to tour the workings of our Austin pipe organ during our History day a couple weeks ago. I never imagined that I would actually get to go inside what amounts to the bellows while the organ was being played.
Here I am inside the "Austin Universal Air Chest."
John Austin filed an application for the patent of his "new" style of windchest design on April 4, 1893. He developed the idea of this new kind of chest in which all of the parts could be seen and repaired even while the organ was turned on and the mechanism was in operation.
The unit gets pressurized and as the organ keys are pressed the little solenoids open valves that let the air go out into the appropriate pipe. If you are inside it makes your ears pop when the pump starts, but it isn't painful or even loud when played. The pipe simply resonates with the air moving out of the chest through it and all you hear inside is just a soft whistling of air blowing out, but outside where the pipes are hold on to your hat! Because in the space where the pipes are mounted it is very loud and sounds awesome!! There are two of these Air Chests, one on each side of the chancel with different banks of pipes for different kinds of sounds.
Just for kicks, here is a link to the American Theatre Organ Societies internet radio station:
Hugs and Blessings,