Before I became wiser, I hated the sound of church organs. In my home church we had a Hammond with little slide things that were pulled or pushed in order to change the sound. They didn't make much of a difference that I could tell and the organ always sounded like mush.
The organ function is to support worship. So when I select registration for a piece, (“registration" is organist talk for the combination of pipes being used) there are some unique sounds available. If the church season is Lent, or the music needs to depict prayer or meditation, using a trumpet just wouldn't be right. Our organ has an oboe or a krummhorn, and I can combine other pipes to create something appropriate. We have about 18 different types of pipes and mathematically that can produce a lot of options. I still find new ways of combining sounds. Coming up with some of these interesting registrations is what makes playing the organ fun for me.
Organ sounds and other things
Hymns require enough volume to support congregational singing, extra volume for the more victorious verses, and pulling out all the stops for the greatest moments. Our organ has several loud, strong pedal options: a posaune, a clarion, and a trumpet. They do a good job of representing depth and strength. Some music I use for preludes and postludes puts the melody in the pedal and the hands play background. That's a different challenge.
One other consideration, some organ pitches and sounds can be annoying or even painful to people who use hearing aids or have some loss of hearing. The aids can be adjusted because generally they are set to help with speech pitch level and upper or lower partial tones can be troublesome. Sitting further away from the pipework may help.
When you look up at the pipework you see square pipes, round pipes—pipes tiny and tall, pipes fat and thin, pipes of metal and of wood. Any group of similar pipes is called a RANK. One complete rank has 61 pipes. The smaller/shorter the pipe, the higher the pitch and the different materials make for different sounds. Our organ has pipes making flute, string, trumpet, oboe, and clarion sounds in addition to pipes making a generic sort of ‘organ’ sound called principals.
The wooden box with shutters is called the SWELL chamber. There’s a pedal on the organ that opens and closes those shutters and that is the only way I can control the volume of the instrument other adding more and more ranks. The upper keyboard is called the swell keyboard and uses the pipes within the chamber.
If you’re still with me, I’ll add that the white tabs above the keys have the names of the ranks of pipes and numbers like 8’ principal, 16’ subbass, or 1 1/3’ flute, 2’, 4’, 32’, etc. and those are about how high or low the pitch is. Now I think it’s weird that some pipes are tuned in such a way that they add an extra something to the sound. A mixture is a combination of several ranks and adds zip and volume on hymns, as in Mixture III. Other unusual combinations can give a lovely sort of shimmer to the sound by utilizing harmonic overtones. That’s a technical term and I’d have to go back to college to explain it.
The King of instruments?
The organ has been called the King of Instruments for various reasons. Mozart was apparently the first to use this description. The very first development of the apparatus dates back to 300 BC, and in its current incarnation it was widely used in churches by 1500. Its largest pipes reverberate through the floors of great cathedrals, but it is able to provide a wide range of expressive sounds. It’s called the king because of the wide variety of sounds and its ability to imitate the sounds of other instruments. It’s similar to having an orchestra at your fingertips.
Speaking of fingertips, the way an organ is played is very different from playing the keyboard of a piano. The sound of a piano key lingers after your finger is removed, and the sustaining pedal can make the sound continue even longer. But the sound of an organ key disappears the moment the finger moves away. So in learning to play the organ, the player has to learn to use finger crossing and finger substituting in order to achieve a smooth, sustained effect. The left hand moves up and helps the right, sometimes playing two manuals with one hand for periods of time. The organist’s shoes are made with small heels so the feet can play more smoothly by using both heel and toe. This also helps play two notes at a time by angling the foot and pressing heel and toe simultaneously.
Thus endeth a short series on the wonders of the pipe organ. Thank you for your interest. If this information piques your interest, see me for a gladly given mini-demonstration.