The Pipe Organ: 8 Facts That May Surprise You
There are many keyboard instruments besides the piano. The pipe organ is one of the most impressive as well as the most challenging. Mozart called the pipe organ “the king of instruments.” Think you know the pipe organ? Read on! Test your knowledge of this versatile keyboard instrument.
1. You can usually see all the pipes in a pipe organ. True or False?
Answer: False. Most pipe organs have several ranks of pipes (groups of pipes organized by timbre and pitch). Most of these pipes are enclosed in a windchest; usually only the main principle stop is visible.
2. The pipe organ is one of the oldest musical instruments still in general use today. True or False?
Answer: True! The basic form of the pipe organ still in use today is essentially unchanged from a keyboard instrument developed in the early 1500’s. In fact, one of the earliest precursors of today’s organ was invented in about 250 B.C. !
3. When an organist “pulls out all the stops” this is akin to…
A. A full choir singing together, with no soloists.
B. A return to the most primitive form of the pipe organ.
C. Turning on all the faucets in your home at once.
D. All of the above.
Answer: D. In its earliest form, the pipe organ had no stops; all pipes played all the time. This is similar to tutti passages in a choir or orchestral work when all parts are being performed simultaneously. To enable the pipe organ to produce more nuanced sounds, a slider was developed which would selectively “stop” air from entering a particular rank of pipes, and therefore prevent that type of pipe from sounding. When an organist “pulls out all the stops,” this enables air to flow through all the organ’s pipe ranks, producing a sound that is full, rich, complex — and usually fortissimo.
4. An “eight-foot pitch” refers to…
A. The length of the pipe for the lowest C on the pipe organ keyboard.
B. A note that is one octave below the four-foot pitch.
C. An extremely poor performance in baseball.
D. Both A and B.
E. None of the above.
Answer: D. The main principle tone for most organs is produced by a rank of pipes whose lowest C results from vibrating an eight-foot column of air. Very often, another rank of pipes produces a C from a four-foot pipe; the notes of this rank are all one octave above the notes produced by the pipes of the eight-foot pitch.
5. There’s no difference between closed pipes and open pipes. True or false?
Answer: False. Open pipes produce the principle pitch and the full range of harmonics. Closed pipes are capped on the top end, and produce a sound one octave below that produced by an open pipe of the same length. In addition, closed pipes produce only odd harmonics (1X, 3X, 5X, 7X, etc.) rather than the full range. Hence the quality of their sound is quite unique compared to that of open pipes.
6. Some of the largest pipe organs may have over 20,000 pipes and 7 keyboards!
7. The term “Swell to Great” describes the organ music of J.S. Bach. True or False?
Answer: False! In fact, the terms Swell and Great refer to two different divisions frequently found in pipe organs. Several ranks of pipes are organized into divisions, and each division usually is played using its own keyboard. If the organ is equipped with a coupler, this allows the stops of one division to be played on the keyboard of another. Hence, the label “Swell to Great” is applied to a coupler which enables the stops on the Swell division to be played using the Great keyboard.
8. Pipe organ wind pressures are roughly…
A. 0.01 psi.
B. 0.1 psi.
C. 1.0 psi.
D. 10.0 psi.
Answer: B, about one-tenth of a pound per square inch. Actually, pipe wind pressures are often measured by organ manufacturers in terms of inches of water! The 0.1 psi mentioned above would equate to roughly 2-3/4 inches of water. This odd-sounding metric comes from a “U-nique” tool used to measure the pressure, a water-filled manometer. This is a U-shaped device containing water, and the metric indicates the relative difference in water level in each of the two legs of the U. Where wind pressure coming out of the organ pipe is greater than the surrounding atmospheric pressure, the water level is pushed downward on the organ-pipe side of the U.
As you can see, the pipe organ is quite a complicated mechanism. No wonder people have been fascinated with this instrument for over 2,000 years!
