Pipes are arranged by ranks. A rank is a complete set, one pipe for each note on the keyboard or pedalboard, of pipes which all have the same sound characteristic. One rank usually equals one stop.
Pipes can be made of wood or metal. Both wood or metal pipes can be open or stopped. Open pipes have a hole in the top of the pipe. In the picture, the first frame contains open flue pipes and the second shows open reed pipes. Stopped pipes have a stopper in the top seen as the dark stick on the top of the wooden pipes in the third frame of the picture. Stopped metal pipes can be identified by the metal cap and felt seal at the top of the pipe. The last four rows of pipes in the fourth frame are stopped metal pipes. Reed pipes can fully stopped or partially stopped but they do not use the metal cap with the felt seal. Metal pipes can also be tapered. Tapered pipes have a conical top as you can see in the last frame. Don't confuse them with the metal stopped pipes in the second row of this frame.
The drawknobs on the organ turn stops on and off. They are labeled with a name, such as Principal, and a number, such as 4'. The name describes the kind of sound and the number tells the pitch range. The organ stops can be complicated to explain. It is easiest to divide the information into two categories: Sound Characteristics and Pitch Levels of Stops.
After you read these sections, you may be interested in additional interesting
information about organ pipes. If you want to see how the organist
controls the pipes, visit An In-Depth Look at the
This site is part of the Pipe Organ Education Project. © Copyright 1996-2001 by Marya J. Fancey.