Spreckles Organ

Spreckels Organ Pavilion was constructed for the 1915 Panama-California Exposition in Balboa Park. It is located at the corner of President's Way and Pan American Road East in the park.
The Organ was built by Austin Organs, Inc. as their Opus #453. It has 73 ranks totaling 4518 pipes and faces north. The audience therefore faces south.
A roll-up steel curtain protects the Organ from sun and rain whenever it is not being played in concerts.
Commercial airplane landings at San Diego's Lindbergh Field occasionally compete with the organ's sound.
Source: Wikipedia