A Bandonion or Bandoneon is some sort of square headed accordion, as I read somewhere.
Well, this is a quite unprecise explanation: Accordion and bandoneon are distinct free-reed bellow instruments. What they have in common is
- they have a bellow
- they are handheld
- they use the same principle to produce the sound: they are free reed aerophones
the sound is produced due to a periodically interrupted air flow using a free reed and a bellow to feed the air flow. Simplified, they belong to a group of bellow driven musical instruments, the harmonicas. The principle will be explained later.
Indeed, it is not easy to distinguish, visually or audible the different existing versions.
One obvious difference is the overall shape and size of the cabinet: it may be square, hexagonal, round, the keyboard: number of keys, arrangements and perhaps the bellow: large and stiff, or long and flexible.
keyboard with the different dispositions or keyboard layouts.
To learn the keyboard is one of the main obstacles for the beginner, particularly if they are learning a double action instrument. While playing the instrument, the keys are located out of visibility and the pupil must learn to hit blindly the right button. It is as learning blind 4 typewriter keyboards.
Bisonor or double action, are those squeeze boxes which produce different notes on pushing and pulling the bellow (closing or opening), formerly classified as diatonic. Those playing only one note for both bellow movements are unisonor or single action, old chromatic. The latter are deprecated today, in the beginning the diatonic instruments had only a few button and not all semitones were present to play a chromatic scale.
A further characteristic is the number of active reeds per button:
The button may act only on one reed, or more than one simultaneously.
Every additional reed gives more options to combine, to alter the sound
or introduce harmonies.
Dual reed boxes are the most common. The two reeds tuned exactly one octave apart, produce a dry sound. It is the way a bandoneon is tuned to be used in tango music. Tuning both reeds one octave apart, but slightly off pitch, a few cent, will result a sweet sound which remembers an accordion. It is used for Bavarian folk music. The acoustic result is a tremolo. An extreme example is the French Musette.
Additional reeds require more space inside the instrument. In fact, their outer dimensions grow rapidly. If more than two reeds per button are used, it is technically not possible to achieve a dry sound. They are practically not suitable for tango. The idea to use more reeds is also to intensify the sound. In pr axis two reed do not sound twice in intensity, but far less; though the air consumption is double. The larger and heavier instrument was found mainly in bandoneon clubs, orchestras with 20 and more members were not seldom.
finally there are models with switchable registers, used to change the sound if required.
If you are looking for a bandoneon to play tango, it is best to select a dual reed double action bandoneon with the keyboard disposition "Rheinische Lage".
This type of disposition was created by Heinrich Band of Krefeld (Rhine)
The last version of Heinrich Band with 130 notes, dated 1860, year of his death, and which later was extended to 142, 152, and one prototype with 178 notes is the result of a particularly well matching of tango music with the sound of the dual reed, octave tuned double action bandoneon.
The bandoneon, of German origin, gained popularity since the middle of the 19th century, mainly because of the genius marketing strategy of Heinrich Band. Eager to accomplishing the needs of the market he pushed the market, publishing the sheet music for the instrument. and a repertory consisting of waltzes, marches and polkas, the popular music at the time and also own compositions.
But there were no few competitors out there, and they tried to copy Band's strategy. similar instruments but with different button distributions invaded the market, claiming having found the definite layout. The truth was, that the learning process took quite long. to solve this inconvenience, they invented a cipher notation writing the key codes instead of the musical notes.
Much later when the tango became a social must in Europe, many accordionists were driven to learn the bandoneon. The solution was to create a bandoneon with a layout similar to the accordion. The Peguri bandoneon with its single action operation became known as the chromatic Bandoneon
A large number of different keyboards were competing. The manufacturers produced more or less on demand. Larger producers tried to impose their system in order to improve performance.
Short before 1900 the bandoneon was discovered to match perfectly well with the upcoming tango. At that time, the instruments of Alfred Band besides those of Ernst Louis Arnold (ELA) the type sold to the Rio de la Plata. These instruments used the rheinische disposition and which became the reference in tango music. Since then the tango developed in a sort of symbiosis with the bandoneon, which had an enormous impact on it's future. During the two world wars, economic and political reasons worked against the bandoneon and it's demand vanished. In spite of new developments, the bandoneon became forgotten.
Fortunately a few outstanding musicians succeeded with a modernized version of the tango, and generated the current tango wave, surprisingly still alive. The bandoneon, got a new chance with the revival. If 20 years ago very few musicians knew the bandoneon, things improved a lot today.