Acoustics – The study of
sound frerquencies, including musical tone and how they intereact with each other and
with physical surroundings. Room shapes, wall, ceiling an floor designs, and building
materials create the acoustic properties of a room. Acoustically live rooms have long reverberation times while the
acoustically dead (dry) rooms with carpet, drapes, padding, acoustical ceiling
tile, and other sound energy absorbing materials may have little or no
reverberation. To support good
congregational and choir singing, a reverberation time of at least 1-1/2 to 2 seconds
is recommended. No echos! Proper
acoustics allow speaking with minimum or no amplification and also allows organ
and congregation and choir voices to blend to create a satisfying musical experience. To understand acoustics effect on musical enjoyment, ask
yourself, “Where does my voice sound better; in a closet with soft absorbing
materials, or in the shower with hard reflective surfaces?
A.G.O. – The American
Guild of Organists. This organization
has set specifications for the standardization of organ consoles, organ
placement, order of stop controls, and proper couplers, etc. The A.G.O. grants
proficiency degrees on the basis of annual examinations: Associate (A.A.G.O.),
and Fellow (F.A.G.O.). It also publishes a monthly magazine called “The
American Organist”.
All Swells to Swell
Switch - This allows for control of all expression pedals with the Swell
pedal only. When used the all divisions expression will be controlled by the
Swell shoe only.
Antiphonal – This organ
division is usually placed at the opposite end of a room from the main organ.
It is used for echo effects, alternating choruses, or for augmenting the main
organ in congregational singing. In
pipe organs, the Antiphonal is a separate division. I digital organs it can be
a division speaking through a separate set of amplifiers and speakers.
Blower – A motor driven
unit that produces a wind supply necessary to produce sound in a pipe organ.
Celeste – Celeste is Latin
for ‘heavenly’. An organ celeste
consists of two eight foot stops played simultaneously with one stop tuned
slightly sharp to the other. The
interaction of the two sounds produces a slow beat or undulation creating an
warm ensemble sound. For example, in a
orchestra there are many violins playing the same note, each instrument having
an ever so slightly different pitch and tone-quality combines to create that
characteristic warm string ensemble sound.
Chest – See Wind Chest
Chamber – A room, usually
open on at least on one side, in which pipes or speakers for the organ are
placed. The open side is often finished
with a decorative grill and grill cloth, and opens into the church or
auditorium. These openings should be as
large as possible. Pipe organs may have
Swell shutters placed in the opening, which when opening and closing, control
the volume of sound heard from the pipes in the church or auditorium. The Swell shutters are operated by the Swell
Shoe (Expression Pedal) with the organist’s foot. Chambers should be finished with hard, ridged, reflective
surfaces like plaster, thick plywood, or double layers of sheetrock painted
with a gloss paint to provide proper tonal egression.
Chiff – The transient
harmonic component that precedes the tone in a pipe voice of flue pipes. This
type of articulation is useful in playing contrapuntal music.
Choir Division – Usually
denotes the bottom keyboard of an organ with three or more manuals. This division operates as an accompaniment
division and also provides the stops for the traditional Postiv division. It usually contains both principal and Flute
ensembles with couplers to increase its flexibility.
Combination Action – Any
device on an organ by which previously selected groups of stops can be
activated by the pressing of a button (piston), or toe stud. The means by which these combinations of
stops are retained in the organ memory are:
1) Pre-sets
– Combinations that do not visibly affect the stops already set. This system is
used on small organs and the stop selections are not programmable or
changeable. They are set at the factory
or can only be changed by a technician.
2) Hold
and Set – The combinations are retained by depressing the desired piston
and holding it in while pulling all the stops desired.
3) Capture
–This refers to the programmable memory in the organ that allows the organist
to set stop combinations assigned to a particular piston for recall as
needed. Capture systems can have as
many as 99 memory levels and 4 to 12 pistons which give the organist over 1000
individual memories.
Compound Stops – Stops
with draw multiple ranks. Roman
numerals indicate the number of ranks drawn, such as “Mixture IV”.
Concert Pitch – An organ
with middle A tuned to a frequency of 440 Hertz (cycles per second). Denoted as “A-440”.
Console – Usually
constructed of fine woods, it can be very plain or extremely ornate. The
console is the organist’s control center or workstation. It contains manual and pedal keyboards, and
stops controls arranged in a standardized and convenient manor specified by the
American Guild of Organists in American, and by other organist organizations in
other countries.
Couplers – There are two
basic types of couplers:
1) Intermanual
– Enables an entire division’s stops to be played on another keyboard, or by
the pedals; sometimes at the same pitch level and sometimes at different
pitches. Examples would be “Swell to
Great 16’”, or “Swell to Choir 8’”, or “Great to Pedal 4’”.
2) Intramanual
– Enable an entire division to be played with itself but at an octave
higher or lower. Examples would be “Swell
to Swell 16’”, or “Great to Great 4’”. Also, an entire division can be silenced
using the Unison Coupler.
3) Within
the above – Sub Couplers are at the 16’ pitch; Unison
Couplers are at the 8’ pitch level; and Super Couplers
are at the 4’ level. Couplers greatly
increase an organ flexibility.
Crescendo Pedal – The
Crescendo Pedal (usually the right-most shoe), gradually adds pre-selected
stops in succession as it is depressed all the way up to full organ.
Diapasons – See Principals
Divided Expression – More
than one expression pedal on the organ so voices on one division may be
controlled, up and down in volume, while voices (stops) in another division are
unaffected.
Division – The traditional
groupings of pipe ranks: Great, Swell, Choir, Solo, Pedal. Each is played from the keyboard named after
that particular division. Having
multiple divisions, each with a separate keyboard allows for rapid changes in
registration as the organist moves from one keyboard to another.
Drawknob – The oldest and
most traditional manner of operating the stops of an organ. A knob with the name of the stop engraved on
it is pulled out to turn on the stop and pushed in to turn it off.
Echo Organ – An Antiphonal
organ usually using softer stops; used for effects of an ethereal nature.
En Chamade – A loud,
horizontal solo trumpet stop.
Enclosed – Pipes located
in an organ chamber or other enclosure with adjustable swell shutters that open
and close to control volume.
Expression Pedal – A
foot-operated pedal, which on a pipe organ opens and closes the shutters of the
swell box (chamber), controlling the volume of an organ division. On digital
organs the expression pedal controls not only the volume, but also attenuates
the higher frequencies of the sounds, giving the characteristic “caged” sound
when closed. On better digital organs,
all of this is adjustable, along with the volume taper at closing and opening.
Extensions – Normally 12
additional pipes added at the bottom and/or top of a pipe rank, allowing that
rank to play an additional octave higher or lower pitch.
External Speakers - Appropriate high quality speakers mounted in a
location away from the console.
Façade – The front display
pipes that are exposed and visible on an organ. These can be decorative or functional.
Finishing – The subjective and artistic process
whereby the various elements of an organ are adjusted, controlled, modified,
and harnessed to provide the musical personality of the instrument. Finishing
on-site must be done by a person with a good ear and knowledge of music. To be finished, an instrument must be voiced
and tuned on each individual stop and individual notes.
Flue Stops – Stops belonging to the Principal,
Flute, Hybrid, and String families of pipes, also called “Labial” pipes. Flues generate their tones by the action of
a sheet of wind which passes through a small gap or flue against a lip in the
mouth of the pipe. This sets a column
of air in motion within the walls of the pipe in the same manor as a whistle.
Flutes – The tonal family
that supports the Principals and also provides another set of tonal colors for
solo and accompaniment voices. Flutes
may be open, stopped, or tapered. Open
and tapered flutes are full-length flue pipes. Stopped flutes speak an octave
lower than their length would suggest because of the cap or stopper which
closes the top of the pipe. The Gedeckt
and Bourdon are examples of stopped flutes.
The Melodia is an example of an open flute, and the Spitzflöte is an
example of a tapered flute. Tapered flutes are narrower at their tops than they
are at their mouth.
Foot (Pitch) – The general
term used to indicate the manner in which pitch is designated on an organ. A rank of pipes, the longest of which is 8
feet long, will produce the standard concert pitch on an organ keyboard;
consequently such a stop is called an 8’ stop.
A 16’ stop speaks the octave below; a 4’ stop speaks an octave above,
etc…
Fractional Pitches – Organ
stops that speak other than unison or octave pitches, that is, 5-1/3’ or 2-2/3’
or 1-3/5’ or 1-1/3’ and others. These
are also called Mutations and are useful in building solo combinations such as
Cornets, but can also add color to ensembles.
Fundamental – The portion
of the musical tone that defines the pitch of the tome to the ear, normally the
lowest pitched harmonic of the tone.
Great Organ – The most
important division of the organ. Other
manual divisions usually couple to it with 16’, 8’, and 4’ couplers. It is characterized by complete development
of the Principal Chorus, the sound most associated with the organ. It is the lower manual on a 2-manual organ
and the middle manual on a 3-manual organ.
Harmonic – Any one if the
many partials that give a musical tone its primary quality is called a
harmonic. The relative intensity of
these harmonics determines the tonal quality of a given sound.
Hertz (Hz) – Frequency of
a wave-form (sound wave) in cycles per second.
Organ tone ranges from 16Hz up to 22,000Hz (22kHz).
Hybrid – Tapered flue
pipes that are midway between String and Principal tone or midway between
String and Flute tone. Examples of these stops are the Gemshorn and the
Erzahler. Hybrid is also sometimes
used to describe an organ using pipe tops and digital stops in the same organ.
MIDI – Musical Instrument Digital
Interface. An international standard developed for the purpose of
playing and linking various instruments.
Standard MIDI connectors are:
1) MIDI IN - Receives MIDI
information from another device.
2) MIDI OUT - Transmits MIDI
information to another device.
3) MIDI THRU - Allows data to
pass through unaltered, which enables many instruments to be connected in
series.
MIDI Sequencer - A piece of digital
hardware/software that can instruct a compatible instrument to switch notes
on/off at whatever velocity they were "recorded". Rather than
recording sound or "audio" it records the parameters of the note. The
sounds triggered are dependent on the MIDI instrument or sampler supplying the
sound. There are up to 16 channels per MIDI loop operating within increments of
0 – 127. M.I.D.I. instructions (e.g.
turn note off, velocity, stop change), are known as "events".
Main Organ – The body of
the instrument usually containing the Great, Swell, Choir, and Pedal
divisions. Echo and Antiphonal
divisions are built elsewhere in the room and are not part of the Main Organ.
Manuals – Keyboards played
with the hands. Organ consoles have
multiple manuals to allow for wuick changes in registration by moving from one
keyboard to another. This also wallows solo
voices to by played with accompaniment by using two or more keyboards at the
same time.
Mixtures – See Compound
Stops.
Mutations – See Fractional
Stops.
Naturals – The “white”
keys of manuals and Pedalboards. (Some
organs will have the key colors reversed.)
Pedal Organ – The organ
division played with the feet. This division provides the bass line and
foundation for the manual registrations and has it’s own solo stops as well.
Pedalboard – The pedal
keyboard, also called Clavier. The
A.G.O. specifies a concave and radiating pedal board of 32 notes, but it can
also be flat non-radiating, or flat radiating.
Percussions – Typical
percussive voices on a classical organ would be Chimes, Glockenspiel, Carillon,
and Harp.
Pipe – The metal and wood
single note wind-blown tone-producing device that is the basis for pipe organ
sound. The two basic types are Flue and
Reed pipes.
Pipe Combination – The
combining of wind-blown pipes with digital voices to create a combination
(hybrid) instrument.
Pistons – Finger-operated
pushbuttons that access the organ’s memory in the combination action. They are
located on the key slips, beneath each manual.
Positiv Organ – An organ
division similar to the Great Organ but lower in the dynamic level. Normally unenclosed, it is used in
combination with or in place of the Choir Organ and is the bottom manual of an
organ with three manuals or more.
Principals – The tonal
family unique to the organ that has no orchestral counterpart. The Principal Chorus (8’, 4’, 2’ together)
is the base to which all other organ voices relate. (Also called Diapason and
Montre)
Rackboard – A flat,
horizontal board with holes in it located on wooden supports immediately above
the toe board of a windchest in a pipe organ.
It is used to support the pipes and prevent them from vibrating and to
keep them standing vertically.
Rank – In pipe
terminology, a rank is defined as a set of pipes possessing a uniform tone
quality, one pipe for each note on the keyboard or pedalboard.
Reed – One of the two
classes of organ stops (also known as “Lingual” pipes). A reed pipe generates its tone by the
vibration of a brass tongue against a rectangular opening, the resulting tone
being given security of pitch and timbre by a resonator placed on the reed
assembly. Reeds are the most colorful
organ tonal family. They can be used in choruses and also as solo stops. Reeds
can range from a very small delicate sound to a huge thundering sound.
Registration – The art of
choosing and combining stops to produce the desired sounds in a specific organ
that will properly enhance the music being played.
Regulation – A voicing
procedure in which each note of each stop is adjusted to assure its proper
relationship to the other notes of the stop, and that stop’s relationship to
the rest of the stops on the organ.
Regulator - See Reservoir
Reservoir – A wind
pressure-regulating device located between the blower and the wind-chests.
(Also see Schwimmer)
Reverberation – The
ability of a room to sustain sound.
This quality is distinguished from an echo, which is an undesirable
repeated bounce between two parallel surfaces.
Reverberation is generally measured in terms of the number of seconds
required for a sound to completely fade away… provides the effect of an
acoustically “live” room. Can be very effective.
Reversible Action – A
device applied to certain critical couplers or stops on an organ that allows
them to be turned on and turned off by the same piston or toestud. Pressing the piston once turns on the
device; pressing it again reverses the previous action. Reversibles are generally applied to manual
to pedal couplers (ex: GT to PD), manual 16’ stops, and pedal 32’ stops. Also used on Tutti toestuds.
Scale – A term used to
describe the diameter of an organ pipe, relative to its length. A larger scaled pipe yields a broader tone,
and a smaller scaled pipe produces a keener tone. The scale of each pipe rank changes within the compass of the rank,
providing each pipe with a unique harmonic character. This varying of the rank’s scale aids the ear in distinguishing
pitch.
Scaling – The process of
determining which scale to use for a particular organ voice. (See Scale)
Schwimmer – A wind
pressure regulation device built into the bottom of many windchests. (Also see Reservoir)
Sequencer – A device that
records, edits, and plays back musical information as MIDI data. (Also see MIDI
Sequencer)
Sequencer Piston – A
piston which when pushed recalls registrations saved in the organ’s memory in a
specific order. This allows for a long
series of stop changes to be made one after the other by pushing only one
piston.
Set Button (piston) – The
piston that is pressed before pressing the piston on which a combination is to
be set. This applies only to Capture Action. (see Combination Action)
Sforzando – See Tutti
Sharps – The (typically)
black keys of manuals or pedals.
Side Jambs – The drawknob
panels beside the manual keyboards that contain drawknobs, or other stop
control, and other controls, arranged by division.
Solo Organ – An Organ
division normally containing only solo stops, played from the top manual of a
four manual organ, or coupled to any division if it is a floating division.
Stop – Strictly speaking,
a stop is a chromatic series of tones of like quality, one tone for each key on
the keyboard. In practice, as
distinction is made between speaking stops and non-speaking stops
(couplers, tremulants, antiphonal controls, expression couplers, etc.).
Stopkey – An engraved
plastic (sometimes wood) tongue that identifies a stop (voice) and actuates
that stop, providing the same function as a drawknob.
Straight Organ – A term
that has historically been used to describe an organ that has a separate,
individual pipe for each note of each available voice on the organ.
Strings – These are
smaller or narrower scaled stop that are subordinate in dynamic level to the
principals and possess a brighter or keener tone. Strings are useful as accompaniment stops.
Sustain – A device that
permits a gradual decay of the tone of a sound. Most commonly affecting MIDI and percussion, but on digital
organs, can be applied to the entire organ to replicate acoustic
characteristics of a larger space.
Swell box – A box with
adjustable louvers on the front. Stops
located within a Swell box are said to be “enclosed” and are perceived to swell
in volume as the louvers are opened an closed.
Swell Organ – The more Romantic division
of the organ named for the fact that it is enclosed in a Swell Box. The Swell contains solo and chorus reeds, as
well as strings and celeste stops. It
is normally the top manual on a two or three manual organ.
Synthetic Reed – Using
mutation pitches on the organ, one can often synthesize reed sounds that are
not actually in the organ. For
instance, flutes at 8’, 2-2/3’, and 1-3/5’ drawn together and played as a solo
voice will make a fairly good Clarinet stop.
A 4’ and a 2-2/3’ flute or an 8’ string and a 2-2/3’ flute can make a
good Oboe stop.
Temperament – The tuning
scheme used in spacing intervals between half tones on a keyboard
instrument. Many temperaments have been
developed, some of which favor certain keys over others. Organs are normally tuned in the most common
temperament, Equal Temperament, where each interval is equal.
Tilting Tablets – Rocker
switches on the console used for turning on and off stops and/or couplers. These switches are normally located on a
board, which is above the organ’s top manual.
On a larger organ with more stops they can be in side-jambs. (Also, see
Stop Key).
Toe Stubs – Foot operated
switches that operate the combination action and are also used for some
reversibles and the Tutti.
Toeboard – The top of a
wind-chest where the pipes stand in holes designed to fit each particular
pipe. Valves are located inside the
wind-chest, under the Toeboard, which open the air passages under each hole
when the proper key is played. This
allows air to enter the pipes causing them to sound.
Transposer – A device that
lowers and raises the pitch of the organ in semitones (half-steps), causing the
organ to play in a key signature different than the key that is being played.
Tracker Touch – A
mechanism applied to the keyboards of the modern organ, which simulates the
top-resistant type of touch characteristic of ancient mechanical (tracker)
action pipe organs. This touch promotes
clean, articulate plying technique.
Tremulant – A device that
causes a rhythmic undulation in pitch and volume that is used as a special
effect most often with a single solo stop.
Each individual manual division has it’s own tremulant.
Tuning – The adjustment of
each pipe (or note in an digital organ) to play at the correct pitch. Pipe tuning is done by changing the length
of flue pipes, usually with a tuning sleeve.
Reed pipes are tuned by changing the length of the vibrating metal
tongues with a tuning wire. The pitch
of pipe organs changes with temperature changes. Pitch will shift about 2-Hertz for every degree F of temperature.
(Higher temp, higher pitch; lower temp, lower pitch.)
Tuning Control – A special
control that allows digital organs to be quickly tuned to a piano or other
instrument, which may not be at concert pitch. (See concert pitch).
Tutti – A reversible
action which, when operated, instantly brings on the full organ. When pressed again, the organ reverts to its
original registration.
Unenclosed – Unenclosed
pipes are located in a visible position and are therefore able to project their
tones directly into the room (vs. enclosed in a Swell box). Frequently, organs will have both the Great
and pedal divisions unenclosed giving them a greater presence and clarity.
Unification – The process
by which a set of pipes is extended and switched to allow for playing at
various pitch levels (16’, 8’, 4’, 2’, 2-2/3’, etc.), thereby increasing the instruments
versatility. (See extensions).
Voicing – The complex
process following the testing of an organ in which every stop in the instrument
is carefully adjusted for correct tonal quality. This involves balancing the stops to appropriate levels, and much
of this is done at the factory, but must be finished on-site.
Wind Chest – An airtight
box containing various actions, which release wind into each pipe according to,
the stops selected and the keys pressed, causing pipes to sound.
Zimbelstern – A mechanical
struck-bell device often located high up in the façade of pipe organs. Modern Zimbelsterns use high-pitched bells
struck by strategically placed clappers to produce a continuous ringing of the
bells, which highlight the tonal colors of the organ. |
