Organ Transplant: Making New Work for One of the Oldest Instruments
Far from being a historic curio, the pipe organ remains an active part of the current classical music scene. In the last several years alone, large pipe organs have been built in several major concert halls and university auditoriums in the United States, and many of these establishments have commissioned new works to inaugurate their instruments.
The organ can seem dauntingly complex to someone who is new to writing for the instrument. The pipe organ is a wind instrument playable by two or more manual keyboards and usually a pedal keyboard. Organ music is generally written on three staves—two for the hands as in piano music, and an extra bass staff for the feet.
The mechanism in a mechanical-action organ is relatively simple. When a key is pressed, it pulls down a long strip of wood called a tracker that opens a valve admitting wind to a pipe or pipes. (The wind was originally supplied by bellows that were pumped by hand.) The valve stays open and the sound remains constant until the key is released. Obviously the keyboards of a mechanical-action organ must be directly under or very near the pipes for the action to work smoothly. With the advent of electricity, blower motors replaced men to pump the bellows. Later electric playing action was introduced wherein the pressure of the key activates a circuit to an electro-magnet that opens the pipe valve. Today builders use both mechanical and electric action. Some new instruments have both, and the player can choose which to use. The main advantage of mechanical action is that the player has direct contact with the pipes and can control not only when they speak but also whether the attacks and releases are fast or slow. The disadvantage of mechanical-action instruments is that the player does not hear the sound the way listeners in the room do. The advantage of electric action is that the console can be placed anywhere, so the player can often hear the instrument in a balanced way. If, however, the console is too far from the pipes, the player experiences a significant delay in the sound that can be disturbing. The player does not have as much control over the touch in electric-action instruments as in those with mechanical action.
The electronic organ is not a real pipe organ, but the console often looks like one. Today the sound is usually produced by digitally-recorded samples from pipe organs. It is then amplified and put through speakers that are installed in the room. The stop knobs or tablets on an electronic instrument have the same types of name and number indications as those on a pipe organ. Some pipe organ builders use digitally-sampled sounds instead of the largest and most expensive pipes in their instruments to save space and money. The specifications of an instrument should tell which ranks are real and which are electronic.
A very important part of the sound of a pipe organ is the room in which it is built and its placement in that room. A reputable organ builder will design an instrument for a specific space and voice the pipes in that space once it is assembled. This is one of the reasons that every pipe organ is different. Part of the amazing sound of historic instruments is that they are often placed high in rectangular, reverberant rooms with thick, solid walls, no padding anywhere, and often under a barrel-shaped ceiling. Unfortunately most American rooms are wide and shallow with a great deal of padding that absorbs sound. A dry room allows for crisp staccato playing and very fast passage-work. Massive effects are disappointing, however. Final notes and chords often have to be lengthened and rests shortened to make up for the lack of reverberation. On the other hand a reverberant room may cause fast textures to be blurred. The reverberation can be used, however, to make lovely echo effects.
Bach Chorale played on the Silbermann organ at Freiberg Cathedral, Germany
Many tone colors are available on the pipe organ. Each of them is produced by a row or rank of pipes, one for each key on the keyboard that activates it. (Pedal ranks have fewer pipes than manual ones because there are fewer pedal keys.) The size and shape of the pipe and the material from which it is made (metal or wood) affect its sound, as with all wind instruments. Each rank of the organ is brought into play by a knob or tablet on the console called a stop. (The earliest organs had many ranks all sounding at once. Levers were added to stop the sound of some of them, resulting in the term “stop” as well as in the common expression “pulling out all the stops.”) Organists usually refer to the size of an organ by the number of ranks of pipes it has.
Each of the different keyboards of the organ, including the pedal, engages its own division of the instrument with several ranks of pipes. The stop knobs on the console indicate in which division the ranks are housed and therefore which keyboard activates them. The divisions are usually separate from each other (above one another, side-by-side, etc.). Often one division, usually called the Swell and played from the top manual, is housed in a box with shutters on it like vertical Venetian blinds that can be opened and closed by the player for subtle dynamic effects. The other divisions are called Great and Pedal on a two-manual organ. If there are three manuals the third is usually called Choir and located below the Great. The divisions may be coupled to each other so that the full organ can be played on one manual (the Great) and pedal.
Organ sound is based upon the blending together of different pitches of the harmonic series. The sounding pitch of each rank is indicated on its stop knob by an Arabic number. Ranks that sound the written pitch are labeled 8′ (the length of an open pipe at low C), those sounding an octave higher are labeled 4′, two octaves higher 2′, etc. Ranks sounding an octave lower than the written pitch are 16′ and two octaves lower 32′. Other members of the harmonic series are also used, resulting in pipes sounding fifths or thirds above the fundamental pitch class.
When these ranks are drawn separately over the fundamental, one hears them individually, but when they are all played together the sound is a complex one that is louder and more colorful than that of a single rank. Often the highest harmonics are drawn together with one stop knob called a mixture. A Roman numeral on the knob indicates how many ranks are being engaged.
A typical American organ will have principals, flutes, strings, and a few ranks of pipes with brass reeds in them that imitate the woodwinds and brass of the orchestra. The basic organ sound is made by pipes called principals (or a similar name in French or German). Principals are generally available at many pitch levels, even on a rather small organ.
Pedal Principal at 16′, with 8′, with 4′, with Mixture, played together
Flute sounds are available at several pitch levels on most organs.
Flute at 8′, with 4′, with 2′
Many organs have pipes that imitate string sound. To copy the sound of strings playing with vibrato, a separate rank of pipes is tuned sharp to beat with the main string sound. It is called a Celeste.
String played alone, with Celeste, with diminuendo made by closing the Swell shutters
Most pipe organs have ranks of reed pipes that imitate orchestral instruments such as oboes, clarinets, and even brasses. The Tremolo, which shakes the wind of the instrument, is sometimes added to reed solos.
The separate high harmonics, called mutations, can be mixed with fundamental pitches to make other piquant sounds as well. The colors available on a particular instrument, called its specifications, will tell the pitch level and placement of each rank. Before writing for any organ, consult its specifications to determine what colors are available. Every organ is different.
The written range of organ music does not reflect the possible pitches available on the instrument, as explained above. Modern organ manuals usually have fifty-six notes (C–g”’) in Europe and sixty-one (C–c””) in the U.S. The pedal keyboard of an organ duplicates the first thirty or thirty-two notes of the manual keyboard (C–f’ or g’). Organ music should be written within this range. Some American builders use the European range, so check the specifications.
Usually an 8′ stop is present in any manual registration to provide the fundamental pitch unless a special effect is desired. A 16′ stop is usually present in the pedal for the same reason, along with an 8′ one to provide more definition. Writing for the pedal is like writing for cellos and basses playing together from the same part. Special effects are available on the pedal (like 4′ alone) but are rare.
Composers have differed widely in their concern for organ registration. The German baroque composers like Bach rarely indicated what stops to use. The French, on the other hand, have always been very particular about tone color and have usually given specific registrations for every piece. It is possible simply to use dynamic markings and descriptive phrases and let the organist register the music. Hindemith did this in his organ sonatas in spite of the fact that his orchestral music is very colorful. Even if specific stop names are used in the music, an organist will have to extrapolate because instruments are all different. Some indications are helpful, like “principals and mixtures” or “solo reed” or “soft flutes.” Obviously the organist would like to know what colors a composer has in mind. Registrations that are very detailed and require a much larger or quite different instrument than the one a player has available may keep a potential performer from playing a piece. Perhaps the best idea is to give general indications of color such as those suggested here.
The most important thing to remember when writing for the organ is that it is the only instrument whose sound is constant in dynamic while the key is pressed, unless the swell shutters are used. A constant sound seems to become louder, as composers of pedal points have always known. Also, most ranks of pipes are voiced to get subtly louder as they go higher in pitch so that the top voice in a full texture will sing through. Therefore if a melody is to be prominent in the tenor range, it has to be registered louder than the surrounding texture.
Organists play with both hands and the toes and heels of both feet. Because there is no way to sustain the sound when the finger or foot leaves the key, music that is to be legato has to be carefully fingered and pedaled. Organists are accustomed to using finger substitution, finger and toe slides, and other tricks to accomplish this. They also often manipulate the releases of notes to give the impression of accents in the music. Many subtle articulations are possible. Articulations should be indicated carefully in organ music as for all wind instruments. If there are no articulation markings, an organist will usually play legato. Pedal parts must be “choreographed” by the organist. The easiest pedal writing to play is for alternate toes, as Bach used in so many fugue subjects. One foot can play scalewise notes with alternating toe and heel, and it is possible to play a third with one foot, but not larger intervals. Slow pedal parts can usually be negotiated by the organist, no matter how awkward, but fast ones should be carefully planned if they are to be successful.
Many different textures are possible on the organ. The organ music of the past was usually polyphonic, often with three voices—one for each hand and one for the feet. This texture can be played on three different colors. A solo melody with some sort of accompanying figuration works well. The melody can be on top, in the middle, or in the bass as in hundreds of organ toccatas. As mentioned above, a fairly slow melody can appear in the pedal in the tenor or alto range, played on a 4′ stop, accompanied by both hands. Because of its sustaining quality, slow music is very effective, but fast music will work too, particularly in the upper registers. (The lower sounds tend to become muddy in a fairly large room.) In Herbert Bielawa’s Pulsar, the two manuals are balanced but different in color. One has a reed in the combination. The pedal also has reeds at 8′ and 16′ to help provide the strong accentuation. The entire texture is staccato with the exception of a few chords near the end.
Pulsar by Herbert Bielawa, performed by Sandra Soderlund, from Pipe Organ Adventures, Albany Records (Troy 374). Used by permission.
Ready to try writing your own work for the instrument? Meet with an organist who can demonstrate what is possible and study the scores of successful organ composers from all periods. In the end, however, sitting at the instrument and trying out ideas yourself is the best learning experience you can have, besides being a lot of fun.
- A Guide to the Pipe Organ for Composers and Others by Sandra Soderlund, Wayne Leupold Editions, Inc., 1994.
- A Young Person’s Guide to the Pipe Organ by Sandra Soderlund with drawings by Catherine Fischer, American Guild of Organists, 1994. (Can be viewed online at www.agohq.org)
- Pulling Out all the Stops: The Pipe Organ in America, video or DVD available from American Guild of Organists
Sandra Soderlund is primarily an organist although she also performs on harpsichord and both modern and early piano. She is organist at the Unitarian Universalist Church of Berkeley and teaches harpsichord and organ at Mills College in Oakland, California. Soderlund holds degrees from Stanford University, the University of Southern California, and Bethany College, Lindsborg, Kansas. She is the editor of scholarly editions of keyboard works, including the Two-Part Inventions and Four Duets of J. S. Bach and the Livre d’Orgue of L.-N. Clérambault, as well as the author of articles on performance practices. Her book Organ Technique: An Historical Approach has been a standard text since its publication in 1980. The expansion of that book, entitled How Did They Play? How Did They Teach? A History of Keyboard Technique will appear this coming summer. She is on the editorial board of the Early Keyboard Journal. Soderlund has given recitals and workshops throughout the U.S., in Holland, Germany, and Korea, and most recently at Notre Dame in Paris. She has recorded for Arkay and Albany Records.