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On Teaching

March 13, 2008
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Gavin Black is director of the Princeton Early Keyboard Center in Princeton, New Jersey. He welcomes feedback by e-mail at <[email protected]>. Expanded versions of these columns with references and links can be found at <http://www.pekc.org&gt;.

Registration and teaching—Part II
In last month’s column, I emphasized the usefulness of starting off the teaching of registration with a clear explanation of the meaning of the foot-designation of organ stops and with a set of demonstrations of that meaning. This is a necessary foundation for understanding everything about combining stops and about choosing organ sounds for music. Once a student clearly understands the meaning of all the numbers on the stop knobs, it is time for that student to begin exploring the art of combining stops. This starts with developing an awareness of what the stop pitch levels imply about the structure of stop combinations, and continues with the development of an ear for the aesthetic nature of different sounds, and then with the acquisition of knowledge about registration practices in different schools of organ composition or in the work of specific composers.
The concept that it is OK to combine stops that are not at the same pitch level as one another, and that the resulting sound will be (or at least can be) a coherent musical sound at a coherent pitch level, is not self-evident. In fact, it is counterintuitive to most people who have not already become well versed in organ registration. It seems, if anything, self-evident that this kind of mixing will result in obvious parallel octaves and fifths, and also in a generalized jumble of pitches, which would at a minimum make clarity impossible (because notes that you play in the tenor register, for example, would produce pitches proper to the treble register, etc.). Since the blending of stops at different pitch levels in fact can work the way it does because of the overtone series, it is useful to explain something about overtones to students. It is certainly not necessary to go into all of the scientific details—the physics of the creation of overtones, the reasons for inharmonicity of overtones in certain situations, or even what the notes of the overtone series are, above the first few. However, it is a good idea to review the basics:
1) Almost all musical sounds produced acoustically have many frequencies blended together. (It usually takes a computer to produce a sound at exactly one frequency.)
2) These frequencies are (usually) a) a given frequency and b) other frequencies that are multiples of that first frequency. (Of course we use the lowest frequency to identify the note, as in “A 440.”)
3) These multiples produce sounds that are related to the lowest frequency by common musical intervals: octave, octave-and-a-fifth, two octaves, two-octaves-and-a-third, etc.
On most organs it is possible to find individual notes on some stops in which some specific overtones can be heard as separate pitches. These can be used to demonstrate the existence of overtones and the pitch levels of some of them. Gedeckts, flutes, and quintadenas are often the most fruitful for this, and notes in the octave and a half or so below middle c are the most promising, because they are the easiest to hear. Usually it is possible to find a pipe or two in which the twelfth is clear (quiet, perhaps, but clear), others in which the seventeenth is, and others in which the octaves are. To someone who has never tried to listen to overtones before, these sounds are usually hard to hear at first, but then suddenly “come in.” The teacher can help with this, first by making sure to zero in on the pipes with the clearest individual overtones, and then by briefly playing, singing, or whistling the actual note corresponding to the overtone that you wish to help the student to hear. This will attune the student’s expectation to that pitch, and it will probably only be necessary for the first few notes.
(A further exercise in listening to overtones is this: play a simple melody on one stop. Try to hear and follow the counter-melody created by the clearest and most noticeable overtones. For example, consider the notes of the fugue subject of Bach’s E-flat major fugue:
b-flat – g – c – b-flat –
e-flat – e-flat – d – e-flat
Depending on what the overtones of each pipe happen to be doing, a counter melody could arise that went like this:
d – d – g – d – g – g – f# – g
or that went like this:
f – b – e – f – b-flat –
b-flat – f# – b-flat
or any number of other possibilities. It will be different for each different stop on which you play the melody. The “extra” melody will be quiet, and usually it will range from one to three octaves above the “official” melody. It is quite possible that these inherent counter-melodies are one source of the human invention of counterpoint. This is all a bit of a detour from learning techniques of registration as such, but it is a useful exercise both for learning to listen carefully to sound and for remembering that sounds themselves are complex and interesting, often doing more than we might at first expect.)
Once a student understands the basic concept of overtones (and believes in them!), it is easy for him or her to understand the blending of stops of different pitches: a 4? stop blends with and reinforces the first upper partial of an 8? stop, a 22?3? stop the second upper partial, a 2? stop the third, etc. One advantage of going through all of this quite systematically is that it answers the question of how in the world it can make sense to combine stops that don’t even produce the same letter-name notes as one another. This is certainly the thing that seems the least intuitive and the most questionable about registration to many of those who are not yet experienced with the organ.
(This can be true especially if someone stops to think about all of the pitches that are present in a thick texture. For example, a G-major 7th chord played on a registration that includes a 22?3? stop includes the pitches g, a, b, c, d, f, f#. If you throw in a tierce you add a d#. That this would be acceptable makes a lot more sense if you know that all of those “extra” pitches are present anyway as overtones.)
So the most basic description of the structure of the art of combining organ stops, and the most useful as a starting point, goes something like this: that, as long as you have one or more 8? stops present in your combination of stops, anything and everything higher than 8? pitch has the potential to blend with the 8? sound. In so doing, it will change the nature of the sound by changing the overall balance of the overtones, and by changing the volume, but it will not upset the pitch identification of the notes that you play.
A simple exercise to demonstrate this would be as follows:
1) choose a keyboard that has more than one 8? stop and several higher-pitched stops.
2) draw the louder (loudest) 8? stop.
3) play a simple passage—a chord progression or a bit of a hymn is good—adding and taking away various 4? and higher stops at random.
4) after a while, remove the 8? stop. The student will hear the music suddenly jump up in pitch.
5) repeat all of this with a softer 8? stop.
Anyone performing or listening to this exercise will certainly notice that not all of the combinations work equally well. Some of the sounds that could blend in theory will not seem to blend very well in practice, perhaps because a 4? or higher stop is too loud or too bright (or for that matter out of tune) or because a given 8? stop is too thin or weak or has something about its intrinsic overtone development that conflicts with rather than supports the addition of higher-pitched stops. These considerations are extremely important. They are also subjective and in the end belong to the realm of artistic judgment or discretion. A student listening to or trying out this exercise should be encouraged to notice aesthetic aspects of each sound. However, the main point for the moment is that the dropping of the 8? pitch makes a sound that is utterly different in kind from the adding or dropping of any higher-pitched stops.
Of course, it might occur to a student, or a teacher might want to mention for completeness if nothing else, that it is perfectly possible to use sounds that omit 8? stops, for some special reason or in some special way. The simplest of these is the use of a 4? or higher sound to play the music at an octave or more higher than the written pitch. Also fairly common is the use of a non-8? registration accompanied by the moving of the hands to a different position on the keyboard to bring the pitch in line with original expectations. These are useful things to bear in mind as a performing organist, but they are special cases that can best be thought about at a slightly later stage in learning, and that should certainly not distract a student from developing the most thorough possible understanding of “normal” stop combination and registration. The same can be said about the use of 16? sound in multi-voiced or chordal manual playing. This, in theory, just transposes the music down an octave, but often doesn’t—for some psychoacoustic or just plain acoustic reasons—quite sound like that.
So far we have developed a rather scientific approach—perhaps too scientific for some people’s taste—to the teaching or learning of registration. We have asked students to think very clearly about the pitch designations of stops, about overtones, about what overtones imply about the use of different pitches of stops, and about how to make sure that a sound is grounded in unison pitch. We have not yet talked about either how to choose registrations that “sound good” (or “beautiful” or “appropriate” or anything else) or about how to respect composers’ wishes or any other way to tailor sounds to pieces. We have also barely mentioned stop names, or even names of important categories of stops, diapasons, flutes, reeds, and so on. Nor have we mentioned any rules or even ideas about how or whether to combine stops of different types, or for that matter of the same type.
Organs have lots and lots of sounds. For example, by my calculations, allowing only for sounds that include 8? pitch and leaving cornets and “céleste” stops out of any ensemble, but taking into account couplers, the Grand Orgue of the Mander organ at St. Ignatius Loyola in New York—a well-known, recent, large but not gargantuan organ—commands 121,889,158,594,564 different sounds. A hypothetical medium-sized organ in which three manuals have 25 to 30 stops would have about 200 million to about a billion 8?-based sounds available in the manual divisions. If the pedal division of such an organ had eight stops, then, assuming normal couplers, the pedals would have a quarter of a trillion different sounds available.
Harpsichords, on the other hand, have rather few sounds. Most large harpsichords have seven to ten different available sonorities all together. Many very fine and versatile harpsichords have only three. In planning registration for a piece on the harpsichord, it is always possible to use what I consider to be the soundest and most artistically thorough approach: simply trying the piece out on every possible sound, listening carefully and with attention, and deciding which sound you like best.
This approach is almost always impossible on the organ. It is always impossible on any organ but the very smallest. However, it seems to me that it is still—albeit only in an underlying theoretical way—the best approach, and the right concept to have in the back of one’s mind when working out registrations. That this is true can, I think, be almost proven logically. If you are using a given registration, whether it comes from an editor, or from your teacher, or from something that you jotted down in your copy years before, or from any other source, but there is in fact a different registration that you would like better if only you heard it, then you should in theory be using that other registration. Therefore, ideally, one would always hear every registration before making a final choice.
(I am not right now dealing with the extra-musical quasi-ethical considerations of authenticity that arise when a specific registration comes from the composer. I will address that at least briefly next month.)
The purpose of taking a student very systematically through what I described above as a scientific approach to the technique of registration—the feet, the overtones, the combinations at different pitch levels—is to allow the student then to feel free to try anything and everything (again, knowing that there won’t really be time for everything!) without fear of doing something that really, in some concrete way, doesn’t and can’t work. This will enable the student to be relatively independent of outside guidelines, and increase the chance that the student will contribute something new and interesting to the world of the organ. It will also almost certainly provide the student with a great measure of out-and-out fun, and keep the job of practicing as interesting as it can be.
Next month I will talk about ways to practice listening to the more subjective, sound-quality-oriented aspects of the blending and combining of stops. I will also talk about helping students to begin to relate sound to other aspects of their concept of a piece of music, and to both structural and historical considerations.?