A concertina is a free-reed musical instrument, like the various accordions and the harmonica. It consists of expanding and contracting bellows, with buttons (or keys) usually on both ends, unlike accordion buttons, which are on the front.
The concertina was developed independently in both England and Germany. The English version was invented in 1829 by Sir Charles Wheatstone, while Carl Friedrich Uhlig introduced the German version five years later, in 1834. Various forms of concertina are used for classical music, for the traditional music of Ireland, England, and South Africa, and for tango and polka music.
Systems
Concertinas are members of a family of hand-held bellows-driven free reed instruments constructed according to various systems which differ in terms of keyboard layout and whether individual buttons (keys) produce the same (unisonoric) or different (bisonoric) notes with changes in the direction of air pressure.
Because the concertina was developed nearly contemporaneously in England and Germany, systems can be broadly divided into English, Anglo-German, and German types. To a player proficient in one of these systems, a concertina of a different system may be quite unfamiliar.
English and Duet concertina
The English concertina and the Duet concertina bear similarities in history and construction. Both systems generally play a chromatic scale and are unisonoric, with each key producing the same note whether the bellows are being pushed or pulled. Both of these English instruments are smaller than German concertinas, and are usually hexagonal in shape, though occasionally featuring 8, 10, or 12 sides. The English system alternates the notes of the scale between two hands, enabling rapid melodies. The duet system features the lower notes on the left, and higher notes on the right, facilitating the playing of interlaced harmonies and melodies.
The English concertina is credited to Sir Charles Wheatstone, who first patented such a design in 1829 in Great Britain. Wheatstone was also the first to patent a duet concertina, in 1844.
German concertinas
German concertinas, developed in Germany for its local market and diaspora, are usually larger than English concertinas, and are generally bisonoric, using a different style of "long plate" reeds, and are often square, as opposed to hexagonal. German concertinas also sometimes have more than one reed per note, which produces a vibrato effect if their tuning differs slightly .
Chemnitzer concertina
Various German concertina systems share common construction features and core keyboard layout. In the United States, particularly in the Midwest where there are many German and Central European descendants, the term concertina often refers to the Chemnitzer concertina, which is bisonoric and closely related to the bandoneon, but features a different keyboard layout and decorative style, including a few mechanical innovations pioneered by German-American instrument builder and inventor Otto Schlicht. A related variant is the Carlsfelder concertina from C. F. Zimmerman, created in 1849 and shown at the 1851 London Industrial Exposition.
Bandoneon
The bandoneon (also rendered bandoneón, bandonion) is a German concertina system with an original bisonoric layout devised by Heinrich Band. Although intended as a substitute for the organ in small churches and chapels, it was soon secularized and is now associated with tango music due to the instrument's popularity in Argentina since the late 19th century when tango developed from various dance styles in Argentina and Uruguay. Though the typical bandoneon is bisonoric, the 1920s saw the development of unisonoric variants such as the Ernst Kusserow and Charles Peguri systems, both introduced around 1925. Bandoneons typically have more than one reed per button, dry-tuned with the reeds an octave apart. "Dry" means that vibrato is absent because the tuning is accurate. The instrument is considered an essential part of the Argentine tango orchestra.