Oops - I forgot about this thread and was 'asleep at the wheel' when newbiehere asked more questions. SORRY newbie! Folks gave some very good answers however.
Though this post goes well beyond the basics, I thought I might as well list some more information for anyone who may be interested... To clarifiy keyboard names:
US/English
Great/Choir/Swell. Sometimes the Choir is called "Chaire" in the U.K.
French
Grand-orgue/Positif/Récit (a.k.a.: Récit expressif)
German
Hauptwerk/Positiv/Schwellwerk
The reason I list them: you may find these names on any instrument in the US! North American builders have a tradition of eclecticism, so it is not unusual to find a bit of a stylistic hodge-podge with stop names and division names.
There has already been some good info on division names - here's some additional info:
Solo: mainly for soloistic melodies; may have some very loud stops; almost always under expression (with its own expression shoe).
Echo: very soft stops; may be located in a remote place, like the ceiling!
Celestial: this is rather rare, but may be similar to the Echo, with stops in the ceiling.
Antiphonal: located at the opposite end of the building.
Bombarde: A French-inspired division containing very loud reeds; also the name of a reed stop.
Rückpositiv: a "postive" organ located behind the organist (usually on the gallery rail).
Brustwerk, Brustpositiv: A diminuitive division usually located right above the keyboard.
There are many other terms found in German organs, perhaps not as easy to associate to an Anglo/American equivalent: Oberwerk, Kronpositiv, etc.
The German terms often have Dutch equivalents, sometimes found in the U.S. Of course, any country has its own version of these names, but they are less found outside of their own country.
For brevity sake (ha! :rolleyes: ) I won't go into Italian or Iberian organs.
Though I should mention the occasionally found term "Trompeteria", which is a division with many trumpets. Some are mounted horizontally, or
"en chamade".You might find a division called "Fanfare", which is similar.
As has been mentioned,
couplers allow the organist to play all of these things simultaneously!
Keyboard order is important: in Anglo/American organs it is almost always Choir (bottom), Great (middle), Swell (top). If there is a manual IV it is usually a Solo/Echo or Antiphonal.
In continental Europe the Romantic/Symphonic organbuilding tradition places the Great on the bottom. The literature written for this tradition is so important that many modern organs are being built with a "manual transfer" that allows manuals I and II to be switched. You might have the Great in the middle to play Bach, and then switch the Great to be on the bottom if you play Franck or Duruflé (whose literature sometimes requires thumbing down from the Récit to the Positif).
In a two manual organ, the Great will invariably be on the bottom. However, I've encountered some tracker (mechanical action) organs with a Rückpositiv on the bottom manual. When in doubt, your main manual will be the one
from which you can play all other divisions (via couplers).
By the way, an organ may have more divisions than keyboards; if you notice a stop called "Echo on Swell" or "Antiphonal on Great" for example, those divisions are said to be "Floating".
Now on to a few other topics mentioned...
The
Tremulant (Tremolo, Trémolo, Tremblant, etc.) is best used for single melodies in the right hand. It is most effective with a flute or quiet reed (oboe). You can also combine pitches such as 8,4,2 2/3, 2, 1 3/5 and use that with tremolo to nice effect. That series of pitches comprises an ancient stop called "Cornet", sometimes listed on its own, single stop. You might also use 8, 2 2/3, 1 3/5, or 8, 4, 2 2/3. It is lots of fun to experiment.
Any stop with a fractional number is known as a
mutation stop. Mutations are part of the harmonic series, and serve to either strengthen the fundamental pitch or more often, to color it. In the previous paragraph I listed most of these you're likely to encounter. Another interesting one is found at 1 1/3', often called
larigot if it is a flute.
Speaking of larigots, the names of stops have very interesting histories, going back as far as the 1400's in some cases. It is worth researching!
Stops with roman numerals are known as compound stops. These are divided into two sorts,
Mixtures and
Cornets. The roman numeral indicates how many ranks, or pipes are sounding when you play a single note. Mixtures most often have unison and quint sounding ranks. Their function is very interesting, and is unique to the organ:
In the bass, a mixture has high pitches to clarify the low note and give it pitch definition. A low chord played on an 8' stop sounds like mud, unless a mixture is drawn.
In the middle of the keyboard, a mixture gives fullness and complexity to the texture. It gives an organ the illusion of being much louder than it really is.
In the treble a mixture plays lower pitches, which give gravity to high notes and keep them from sounding screechy.
The way that a mixture accomplishes all this is to "break back" as it ascends the scale. If you draw a mixture stop alone, then play an ascending chromatic scale, you will discern how it breaks back, almost like a car shifting gears.
Mixtures are quite helpful when playing hymns and accompanying congregational singing.
Cornets are not used to accompany singing - they are better for solo melodies or for strengthening chorus reeds (trumpets, bombardes, tubas) in the treble.
It sounds like newbiehere was in luck with those preset pistons (graduated in volume), and especially with the "manual bass". That last feature was invented specifically for pianists without pedal skills!
One last comment: there is a special effect stop known as a
"Celeste"; (not to be confused with the
"Celesta", which is a percussion stop in the organ similar to its orchestral equivalent). The Celeste is usually paired with a similar stop and is usually a string-toned stop (Gamba, Salicional, Gemshorn, Viola, etc.). The idea is to draw the string stop with its celeste partner. The string stop is in tune and the Celeste is typically tuned sharp. Together, they create a mysterious floating quality useful for meditative music - especially slow, chordal music. The character of the string stops and the amount of "celesting" will determine if the effect is tranquil or more energized.
One of the few "no-nos" of organ playing: do not use a celeste in fuller combinations. Once you reach mezzo-forte, the celestes should be off (as should probably be the string stops too).
Unless you are playing a Wurlitzer, the tremolos should be off too.
OK, enough for now...