Additional Information About Pipes

Stops Are Divided into Groups

Stops are grouped in division which means that stops in the same division are in the same spatial location. Common division names are Swell, Great, Positive or Choir, and Pedal. Each manual controls its corresponding division and the pedal controls the Pedal division. Reed and flue pipes of all pitches are included in all divisions. When the organ is small and only has one or two reeds, these reeds are usually distributed with one in the swell division and one in the great division. On the manuals, the organist has stops from 16' to 1' available. There are usually only one or two 16' manual stops. Among the manual divisions, the Great is the "heart" of the organ so it has the strongest stops. The Swell and Choir frequently contain soloistic stops. The Choir's reed stops are more mellow than the swell's. The Positive is similar to the great but not as strong and usually has the most mutations (stops with a mixed number like 1 1/3').

The Pedal has a heavier concentration of 16' stops than the manuals because the pedal has a different function in organ music. It can have higher pitched stops such as 4' and 2' as well. Room space often dictates the number of stops an organ can have so if there is not enough room for a lot of pedal stops, the pedals may only have 16' and 8' stops available. A large organ may include solo stops in the pedal division. There are many pieces in organ literature which use a solo stop to play the melody in the pedal.

CouplersCouplers from the Holtkamp at the University of Kentucky

Couplers allow stops from different divisions to be played by a single manual. It is similar to a copy command in a word processing program. For more on couplers, see A Closer Look at the Console.

Registration

The organ is divided so that each division will have a variety of possible registrations, the choice of stops and couplers which the organist uses in a piece of music. Sometimes, the composer specifies the registration in the score. If the organ does not have the same exact stop names that the composer wants, the organist substitutes a similar stop. For example, principal pipes have many different names so if the composer asks for an 8' Open Diapason, an 8' Montre can be substituted. The Montre does have a different tonal quality than the Open Diapason but they are close enough so that the musical effect is still close to what the composer wanted. However, substitution does not always work well. Some organ works use so many stops that they can only be played on large organs. The organist learns how to make registration decisions through experience. Learning how to register a piece is just as important as learning how to play the notes.

It is common to use several stops at once. Some combinations of stops are so commonly used that they have names. Sometimes composer simply use the registration term instead of naming all the stops used. Here are some examples.

Chorus: Just as a choir is a mix of different voice ranges (soprano, alto, tenor, and bass), a chorus on the organ is a mix of different pitch levels. Choruses are usually 8', 4', and 2' pipes. A flute chorus uses these flute stops of these pitch levels. A principal chorus uses principal pipes of these levels and also uses the compound or mixture (labeled with a Roman numeral). A well-designed organ will have a chorus on each division, each with a slightly different character and volume.

Foundations: This is the opposite of a chorus. Foundations use all 8' stops in the manuals, except the celestes, and all 8' and 16' stops in the pedal. Only flue pipes (principals, flutes, and strings) are used. French Romantic composers frequently include a manual 16' from the Great division as part of the foundation registration.

Cornet: This is a cornerstone of French Baroque registration. The cornet uses an 8' flute, 4' principal, 2 2/3', 2' principal, and 1 3/5'. The resulting sound is like a coronet and is frequently used as a solo stop. It is not as bold as a reed stop but it has similar characteristics. It is an excellent example of how mutations can be effectively used.

There are many more types of registration but there is not room to list all of them. Organists in graduate programs are expected to know registration so well that they cannot pass their oral exams without demonstrating knowledge of specific registrations.

Artistry in Organ Playing: Controlling the Sound

The organ is a complex machine operated through the console. The challenge for the organist is to make musical sounds, not mechanical ones. Choice of registration, opening or closing the expression pedals, playing on different manuals (thus using different divisions), and changing registration (by hand or with pistons) are the mechanical controls which the console offers. Learning to control the console is an important part of one's organ technique. In addition to these console controls, the organist can be expressive through the ways in which the notes are played. Notes played legato, or smoothly, give a different effect than those played detached. Stretching the tempo will also give the music a new perspective. Different styles of playing have emerged from the different historical periods in music. Today's organists are expected to know the different stylistic approaches and be able to play in a variety of styles. Understanding how the pipe organ works is the first step to playing with more expression.
Glossary Resources

This site is part of the Pipe Organ Education Project. © Copyright 1996-2001 by Marya J. Fancey.