The sculptural spouts on the facade account for only 126 of the 6,134 wood and metal pipes, the remainder of which are enclosed in the Douglas fir frame. The tubes vary in length from one-quarter inch to a 32-foot “flute” that hangs upside down along the back wall so it can be tuned more easily.
Shutters along the organ’s frame control the volume. Opening the “blinds” increases sound by exposing the pipes inside.
Three cast-iron blowers that put out 15 horsepower in a room behind the frame generate the wind that makes the organ sing. The air travels through one of three pressure-static wood compartments before reaching the pipe chambers.
There are four 61-note keyboards. Each connects to one of the Opus 24’s five chambers (foot pedals connect to its fifth). When a key is played, an electrical impulse sends air to the pipes, which produce a note.
The organ is played at two desklike consoles. A Panasonic camcorder and monitor sit atop the main terminal so the organist can see the conductor. A recording device in the drawer of the second console saves performances onto a floppy disk.
The 128 porcelain knobs surrounding the keyboards open and close the pipes. The phrase “pulling out all the stops” derives from the engaging of multiple valves.
The 252 hard-to-spot stainless steel struts and pins lend structural support to make the Opus 24 earthquake proof. They’re secured to exterior pipes and run along various points of the facade.