How a Pipe Organ Works

Simply Stated…

Cross section of a pipe organ
Interior view of a pipe organ
Dom Bedos

…the pipe organ is a big box of whistles. Each pipe sits on top of a hollow wind chest that is filled with compressed air provided by a bellows or blower. Each ‘stop’ at the organ console represents a set of pipes (a rank) of a particular tone color, with a different pipe for every note on the keyboard. Pulling the stop activates a slider under that specific set of pipes on the windchest, making them available as a sound-source. The wind chest also contains a series of valves (pallets) connected to the keyboard by a mechanical linkage. These pallets govern the flow of air to each pipe, and even though a stop may be on, no pipes will sound until a key is depressed and its respective pallet opens. This allows the compressed air to pass up through the pipe for that note, creating sound.

organist and bellows illustration
Organist on the bench & an assistant pumping the bellows
Dom Bedos

Organs are unique

One trombone is likely to look like any another trombone and most violins are virtually identical, but each pipe organ is unique. (Just look at the variations in our gallery.) Each pipe organ is custom made for the buyer, and in every case a number of variables need to be addressed. Considerations for each new instrument might involve the number and types of sounds included, the size of the room where the organ will be placed, the physical look of the instrument and also, the budget.

How a pipe organ works
How a Pipe Organ works
Smithsonian magazine