bandoneon

thumb|(play) A bandoneon playing modern tango thumb|Early bandoneon, thumb|Alfred Arnold bandoneon, The bandoneon () or bandonion is a type of concertina particularly popular in Argentina and Uruguay, used in most tango ensembles. As with other members of the concertina family, it is held between the hands, and played by pulling and pushing air through bellows, routing it through sets of tuned metal reeds by pressing the instrument's buttons. Unlike most accordions, bandoneons always employ the same sets of reeds to produce their sound, and do not usually have the register switches common on accordions. Nevertheless, the bandoneon can be played very expressively, using various bellows pressures and other techniques. The left and right hand have different timbres due to the wooden box on the left side which gives the left hand a nasal and muted timbre, in contrast with the right hand which is usually bright and sharp.

==History== The Bandonion, so named by the German instrument dealer Heinrich Band (1821–1860), was originally intended as an instrument for religious and popular music of the day, in contrast to its predecessor, the German concertina (), which had predominantly been used in folk music. It is believed that around 1870, German and Italian emigrants and sailors brought the instrument to Argentina, where it was adopted into the nascent genre of tango music, a descendant of the earlier milonga. However, there is no documentation of how exactly the bandoneon was introduced to the Rio de La Plata region. The instrument was also adopted in to genres such as the Chamamé.