![reedsinset](https://upload.wikimedia.org/wikipedia/commons/8/8f/Reedsinset.jpg)
A reed rank inside an
accordion
Accordions (from 19th-century German ''Akkordeon'', from ''Akkord''—"musical chord, concord of sounds") are a family of box-shaped musical instruments of the bellows-driven free-reed aerophone type (producing sound as air flows past a reed ...
is a single full set of the
reeds that are the means to achieve the instrument's sound range. These reed ranks are located in the reed chamber. Most accordions to this date typically have between two and four reed ranks on the
treble side and between three and five reed ranks on the
bass side. These can usually be selected individually or combined in various ways to provide a range of different
timbre
In music, timbre ( ), also known as tone color or tone quality (from psychoacoustics), is the perceived sound quality of a musical note, sound or musical tone, tone. Timbre distinguishes different types of sound production, such as choir voice ...
s, by use of register switches arranged by
register
Register or registration may refer to:
Arts entertainment, and media Music
* Register (music), the relative "height" or range of a note, melody, part, instrument, etc.
* ''Register'', a 2017 album by Travis Miller
* Registration (organ), th ...
from high to low. More of the top-line expensive accordions may contain five or six reed blocks on the treble side for different
tunings, typically found in accordions that stress
musette
Musette may refer to:
Music
* Musette de cour, or baroque musette, a musical instrument of the bagpipe family
* Musette bechonnet, a type of French bagpipe
* Musette bressane, a type of French bagpipe
* Oboe musette, or piccolo oboe, the small ...
sounds.
How many reeds an accordion has is specified by the number of treble ranks and bass ranks. For example, a 4/5 accordion has four reeds on the treble side and five on the bass side. A 3/4 accordion has three reeds on the treble sides and four on the bass side.
Reed ranks are classified by either
organ 'foot-length'
stop
Stop may refer to:
Places
* Stop, Kentucky, an unincorporated community in the United States
* Stop (Rogatica), a village in Rogatica, Republika Srpska, Bosnia and Herzegovina
Facilities
* Bus stop
* Truck stop, a type of rest stop for truck d ...
s or
instrument names. Visually, they each have a fixed dot in a three-level icon as displayed in the photo on the right and tables below. These icons display when more than one reed-rank is in use.
Register stop classifications
The pitch of a single bank of reeds is traditionally defined in a similar manner to the
organ stops
An organ stop is a component of a pipe organ that admits pressurized air (known as ''wind'') to a set of organ pipes. Its name comes from the fact that stops can be used selectively by the organist; each can be "on" (admitting the passage of ai ...
of a
pipe organ
The pipe organ is a musical instrument that produces sound by driving pressurized air (called ''wind'') through the organ pipes selected from a keyboard. Because each pipe produces a single pitch, the pipes are provided in sets called ''ranks ...
. A bank that sounds at
unison pitch when keys are depressed is called
8′ (pronounced "eight-foot") pitch: alluding to the length of the lowest-sounding organ pipe in that rank, which is approximately eight feet. For the same reason, a stop that sounds an octave higher is at 4′ pitch, and one that sounds an octave lower than unison pitch is at 16′ pitch.
Most reed registers are normally in relative
octave
In music, an octave ( la, octavus: eighth) or perfect octave (sometimes called the diapason) is the interval between one musical pitch and another with double its frequency. The octave relationship is a natural phenomenon that has been refer ...
tuning, but rarely, some instruments have a reed bank tuned to a
perfect fifth
In music theory, a perfect fifth is the Interval (music), musical interval corresponding to a pair of pitch (music), pitches with a frequency ratio of 3:2, or very nearly so.
In classical music from Western culture, a fifth is the interval fro ...
relative to the 8′ stop (or some octave of that) such as the
Bayan (accordion)
The bayan ( rus, бая́н, p=bɐˈjan) is a type of chromatic button accordion developed in the Russian Empire in the early 20th century and named after the 11th-century bard Boyan.
Characteristics
The bayan differs from western chromati ...
in the new models. This is a similar arrangement to stops for a
pipe organ
The pipe organ is a musical instrument that produces sound by driving pressurized air (called ''wind'') through the organ pipes selected from a keyboard. Because each pipe produces a single pitch, the pipes are provided in sets called ''ranks ...
.
On accordions with two 8′ ranks, one is tuned a fraction of a
semitone
A semitone, also called a half step or a half tone, is the smallest musical interval commonly used in Western tonal music, and it is considered the most dissonant when sounded harmonically.
It is defined as the interval between two adjacent no ...
(usually no more than 25
cents
) higher than the other ranks. This causes
beats when the two 8′ ranks sound together, creating a distinctive
tremolo
In music, ''tremolo'' (), or ''tremolando'' (), is a trembling effect. There are two types of tremolo.
The first is a rapid reiteration:
* Of a single Musical note, note, particularly used on String instrument#Bowing, bowed string instrument ...
timbre
In music, timbre ( ), also known as tone color or tone quality (from psychoacoustics), is the perceived sound quality of a musical note, sound or musical tone, tone. Timbre distinguishes different types of sound production, such as choir voice ...
.
Tunings where the difference between the two is small and the beats are less noticeable are referred to as "dry", whereas those where the difference is large are referred to as "wet".
Accordions with three 8′ ranks have the third tuned the same distance below the center, doubling the effect of the beats when all three play.
:
Register switches
Register
Register or registration may refer to:
Arts entertainment, and media Music
* Register (music), the relative "height" or range of a note, melody, part, instrument, etc.
* ''Register'', a 2017 album by Travis Miller
* Registration (organ), th ...
switches select combinations of reed ranks to produce contrasting
timbre
In music, timbre ( ), also known as tone color or tone quality (from psychoacoustics), is the perceived sound quality of a musical note, sound or musical tone, tone. Timbre distinguishes different types of sound production, such as choir voice ...
s. Most accordions have automatic or preset switches, similar to voice selection on an electronic keyboard, or (more precisely) to a preset
combination action
Registration is the technique of choosing and combining the stops of a pipe organ in order to produce a particular sound. ''Registration'' can also refer to a particular combination of stops, which may be recalled through combination action. The ...
in a
pipe organ
The pipe organ is a musical instrument that produces sound by driving pressurized air (called ''wind'') through the organ pipes selected from a keyboard. Because each pipe produces a single pitch, the pipes are provided in sets called ''ranks ...
. These switches control which reed ranks are enabled (opened up) or disabled (closed off): some switches enable a single reed rank, others enable several simultaneous reed ranks. In general, the formula for the number of potential switch combinations is one less than 2 to the number of unique reed blocks that are within the accordion. For example, if an accordion has 3 reed blocks, there are potentially 2-1 = 7 combinations, though "less useful" ones are often omitted.
[Strictly speaking, there are 2 combinations (8 from 3 reed blocks), but the one with all ranks closed is only useful in organ accordions or MIDI accordions where it may be desired to play the electronic voices only. This can be seen on a "Closed" switch with no dots.] Unlike individual
organ stop
An organ stop is a component of a pipe organ that admits pressurized air (known as ''wind'') to a set of organ pipes. Its name comes from the fact that stops can be used selectively by the organist; each can be "on" (admitting the passage of air ...
s, only one combination is active at any given time.
Here are a few examples of right-hand manual switches on a typical large accordion.
(Smaller instruments with fewer reed banks may have fewer switches or even none.)
:
![Excelsior 00 accordion rocker switches detail](https://upload.wikimedia.org/wikipedia/commons/1/1e/Excelsior_00_accordion_rocker_switches_detail.jpg)
Instead of automatic switches, some accordions have individual switches for the reed ranks that can be used in any combination, like
organ stop
An organ stop is a component of a pipe organ that admits pressurized air (known as ''wind'') to a set of organ pipes. Its name comes from the fact that stops can be used selectively by the organist; each can be "on" (admitting the passage of air ...
s.
In addition to the master switch located with the other switches shown above, professional-grade accordions often have at least one extra master switch: either a ''chin master'' at the top of the instrument or ''palm master'' switch located at the side of the keyboard. These allow for faster changes to the register while the right hand is playing the melody. Some have double bassoon (16′ + 16′), equivalent to a tenor violin, and the tenor musette (16′ + 16′ + 8′) is also found in some model accordions.
Cassotto
High-end accordions often have a feature called a ''cassotto'' (Italian for "box"), also referred to as a "tone chamber", in the treble (right-hand) reed section. In this design, certain reed sets (usually one set of middle reeds, and the set of low reeds) are mounted at a 90° angle to the remaining reeds. The sound from these specially-mounted reeds must then travel farther, and along a different path, before leaving the instrument, muting its
harmonics
A harmonic is a wave with a frequency that is a positive integer multiple of the '' fundamental frequency'', the frequency of the original periodic signal, such as a sinusoidal wave. The original signal is also called the ''1st harmonic'', ...
(''partials'') and creating a distinctively mellow, refined sound. The sound of cassotto bassoon (low) reeds is particularly favored by
jazz
Jazz is a music genre that originated in the African-American communities of New Orleans, Louisiana in the late 19th and early 20th centuries, with its roots in blues and ragtime. Since the 1920s Jazz Age, it has been recognized as a major ...
accordionists.
The cassotto design requires a sophisticated treble mechanism where each key must open and close air passages not only for reeds mounted at the traditional angle, but also for air passages at a relative 90° angle (for the cassotto reeds). To do this properly, each rod and pad must be positioned precisely in relation to its perpendicular counterpart. Because of the considerable extra time required for the cassotto's construction and adjustment, cassotto accordions cost considerably more than similar non-cassotto models.
References
Notes
{{DEFAULTSORT:Accordion Reed Ranks and Switches
Accordion
Musical instrument parts and accessories