Pipe Organs
Created | Updated Sep 20, 2016
Joking apart, Prince Albert had asked me to go to him on Saturday at two o'clock, that I might try his organ before I left England.
- Felix Mendelssohn Bartholdy
The pipe organ is one of the most complex constructions ever built by pre-electronics humankind. It is also the loudest musical instrument by far: the organ in the Royal Albert Hall, London, is driven by a 42 horsepower pump and is capable of drowning out an entire symphony orchestra. An organ can have as few as 48 and as many as 25,000 separate pipes. Each of these produces a note. They can be played singly or in combination to get different tones. A typical concert hall organ, such as the one in the National Concert Hall, Dublin, has over 4,000 pipes.
The organ has been associated with church music for a long time. From the 17th to the 20th Century, it was considered the only suitable instrument to be played in 'God's house'. It is also the traditional favourite of vampires and opera phantoms. Any time you see a dark castle in the rain, or a house with turrets and gargoyles, you can be sure there will be an organ playing nearby.
How it Works
The basic principle of the organ is a box full of high-pressure air connected to a cylindrical pipe. Pressing a key on the keyboard releases air into the pipe, which produces a musical note in the same way as a flute or clarinet.
The keyboard, known as a manual, has typically 49 - 61 keys (four to five octaves). There will be the same number of pipes in a set, known as a 'rank', as there are keys on the manual, and each pipe is connected to a different key. But there will also be other ranks of pipes connected to the same keys. A mechanism called a 'stop' will turn on or off a whole rank at the same time, so you can play from any or all the ranks simultaneously.
Construction
The main components of the pipe organ are as follows:
The windchest and bellows - the windchest is a box which is filled with high-pressure air, also known as wind. All the pipes are fed from it, so the more pipes there are, the bigger the box needs to be. The windchest must be kept pumped up with air: in modern organs, this is done by electric fans, but in the old days, bellows were used and these were generally hand pumped by assistants at the back of the organ. Chords, that is, a large number of notes played at the same time, were not recommended in organ music because the poor guy round the back would be exhausted providing air for a large number of pipes. This meant that organ music tended to use arpeggios instead - broken chords, the notes of the chord played one at a time in sequence. The full chords were reserved for the end of the piece, after which the exhausted bellows man could take a well-earned rest.
Sets of pipes known as ranks - each rank produces a different sound. Some might sound delicate and reedy, others might be big and brassy. Ranks of organ pipes are usually named after the sound they most resemble, so there are ranks with fanciful titles like chalumeau, bombarde and vox humana1 but the resemblance can be quite hard to hear - most of them sound like organ pipes. Percy Scholes, in 'The Oxford Companion to Music', describes the vox humana as usually resembling 'a discouraged goat'. The most common types of pipes are the reed, the flute and the diapason. The diapason is the sound most people associate with organs.
Manuals - the keyboard of an organ is called a manual, because it is worked by your hands. Unlike a piano, which has one keyboard, an organ normally has at least two and may have up to four2. Different manuals may control different ranks of pipes so you can play a trumpet sound with your left hand and a flute with your right. The main two manuals are called the 'Great' and the 'Swell', with the Swell positioned above the Great.
Stops - a stop is a control which turns on or off a complete rank of pipes. It looks like a doorknob, and is above or beside the manuals. Pulling the stop out turns on the rank of pipes, and pressing it in turns them off. Playing with 'all the stops out' will turn on all the ranks at the same time, producing the loudest possible sound from the organ.
An organist friend of mine pointed out that in the Doctor Who episode 'The Lazarus Experiment', the Doctor uses the organ of Southwark Cathedral to fight a monster. At the crucial moment, he shoves all the stops in and plays an earsplitting noise, confusing the monster. This would in fact have turned off the sound. He should have pulled out all the stops. But perhaps it looked better this way on screen.
Pedalboard - as wells as keyboards operated by the hands, there is often a keyboard operated by the feet. This is called a 'pedalboard' and usually has about two and a half octaves.
Console - the place where the organist sits, with its collection of manuals, pedals and stops, is called the console. The console is usually near the pipes, but can in fact be quite distant from them. For example, in St Fin Barre's Cathedral in Cork, Ireland, the console is beside the altar, but the pipes are in a pit in the West Gallery of the cathedral. With modern electrical connections between the console and the pipes, there is really no problem in separating them. Some organs, such as the one in Liverpool Anglican Cathedral, have two complete consoles, each controlling the organ - performances can be given from whichever is convenient.
The Swell Pedal - normally the organist has very little control over the volume produced. Some pipes play quietly and some play loud, so the player can choose to play quietly by selecting a rank of pipes that are naturally quiet. But that's about it. Some ranks, however, do have a volume control, in the form of a device like a Venetian blind in front of the rank of pipes. This is connected to a 'swell pedal' which the player works like the accelerator in a car to turn up and down the volume. The swell pedal normally only controls notes played on the Swell manual. Other manuals all produce full volume.
Production of the Sound
There are two main means of sound production in a pipe:
In a 'flue' pipe, the air strikes against a hard edge known as a wedge, which produces noise. This resonates in the pipe, which is usually cylindrical but may have a conical taper to it. A note is produced whose pitch is dependent on the length of the pipe.
In a 'reed' pipe, the air strikes against a piece of metal known as the reed, which is free to vibrate. The vibrations cause resonance in the pipe and produce a note whose pitch depends on the length of the pipe and also on the vibrating properties of the reed. Reed pipes produce a buzzier sound than flues.
In either case, the longer the pipe, the deeper the sound produced. Pipes lengths are usually given in feet. The standard pipe is known as an 8-foot pipe because the lowest pipe in the rank is eight feet long. A 4-foot pipe will produce a note an octave higher and a 16-foot pipe will be an octave lower. Really massive organs may have 32-foot or even, very rarely, a 64-foot pipe. The latter produces notes so low that they are right on the limit of hearing, being more felt than heard.
In addition to the two basic types of pipe, flue and reed, there are all sorts of ways of getting different tones from the pipes, such as making them from wood or metal, changing the shape of the pipe, and blocking one end of the pipe.
Music
Hope yours does too
– Graffiti on a poster advertising 'Bach's Great Organ Works'
JS Bach - Toccata and Fugue in D minor. Bach went through a phase of writing mainly organ music, and his works are considered among the best things ever written for organ. The Toccata is the best known piece by Bach and is instantly recognisable to most people, although they may not know the name of it.
Charles-Marie Widor - Toccata. Widor wrote a lot of organ music, including 10 symphonies for solo organ and another 3 for organ and orchestra. His Toccata is probably his most famous work. It is the final movement from the Symphony for Organ No 5, but is often played on its own as a show piece.
Handel - Organ Concertos. Handel wrote lots of these. They have a wonderful interplay between organ and orchestra.
Elgar, in his 2nd Symphony, and Saint-Saëns, in his 3rd Symphony, use the organ as a bass foundation for the orchestra, adding a bit of oomph. The Saint-Saens symphony is known as the 'Organ Symphony' for this reason, although the organ does really not have a lot to do in it.
The two pieces which are probably best known are the Wedding Marches by Wagner and Mendelssohn, often played at the start and end of church weddings. These were in fact not written for organ but are arrangements of a piece from an opera (Lohengrin) and the incidental music for a play (A Midsummer Night's Dream) respectively.
Mechanical Problems
As mentioned earlier, organs are mechanically extremely complex beasts, far more so than any other musical instrument. They deteriorate with age and suffer from air leaks from reservoirs and pipework, deterioration of leatherwork, wood splitting, vermin damage, general accumulated dust and dirt, and even tin pest. As a result, they need regular maintenance and periodic renovation. The organ in the Royal Albert Hall, for example, recently had a major refurbishment, which put it out of service for two years. The work was completed in 2004 and now, for the first time in ages, the organ is capable of being played to its full extent.
My friend's daughter was doing an important musical examination on her local church organ. Unfortunately, the organ was undergoing refurbishment at the time, and the stops were not connected to the pipes. The maintenance man had to sit inside the organ. When the player moved the stops, the repair man would manually pull the appropriate levers.
Organists
Playing the organ looks at first sight just like playing the piano. But it is not so. It comes as a great shock to pianists when they tentatively play their first few notes on the organ, as there is no such thing as 'tentative' on the organ. Any key pressed down will play a note at full blast and will continue to do so until the key is released. Organists must learn precision both in starting and finishing their notes.
Organists are unlike other musicians. For most of their performances, they are the only instrumentalist present, because most organ music is performed in churches with just the organ and singers. They play with their backs to everyone else and observe the conductor, if there is one, through a tiny mirror about the size of a shaving mirror. Perhaps because of this, many organists have a slightly more relaxed attitude to strict tempo than other musicians. They find it easier to listen to the choir and keep with the singers than to look at the conductor. This problem is made worse by the fact that if there are other musicians in the church, they will generally be positioned quite some distance from the organ pipes, so there will be a time delay between their sound and the sound of the organ. This makes it something really special when an organist can play exactly in time with the orchestra.
'Registration' is a process the organist must carry out before a concert, where the most appropriate sets of registers must be chosen for different parts of a performance. While the full-throttle sound is suitable for a glorious finale, other sounds must be chosen for quiet, mournful or cheerful sections of the music. This can be quite a complex task on a large organ. Modern concert organs usually feature a diskette drive or similar device so that these registrations can be stored for use in later performances.
Partners of organists get used to having their shins kicked under the breakfast table as the organist practises the foot movements for the pedal board.
Electronic Organs
The organ was one of the first musical instruments to be simulated electronically, and electronic organs are popular enough in bands. The Doors used a Hammond Organ in many of their hits. The electronic sound is a good one, but it is not usually considered authentic enough for performances in church or concert hall. Nevertheless, many parts of the modern pipe organ are under electronic control. The keys and stops may all be linked electronically to the devices that release the air into the pipes, allowing stop settings to be changed quickly and stored electronically for later use. Many modern organs have buttons below the manual which can be reached with the thumb without removing the player's hands from the keyboard, allowing quick changes of stops in the middle of a piece. This was extremely difficult to achieve in the days of mechanically operated organs.
