he heart of Tango music is the bandoneon instrument. It has been said that “the bandoneon and tango are but one and the same thing”. Of German origin, it used to be the instrument replacing the organ in the Lutheran churches of humbler communities where services were sang and organs could not be afforded. It was adopted by “Tangueros “ at the beginning of the 20th Century in order to replace the flute and complete the unmistakable sound of Tango. Fatulo Castillo says that : “the bandoneon gives Tango the sounds of lament and its inclination towards moaning and grumbling”.
The bandoneon gave Tango a definite, complex form, integrating melody into a simultaneously rhythmic and harmonic base. This melodic-rhythmic-harmonic complexity will later be strengthened by the piano replacing the guitar and the development of a new “tanguera” technique founded on rhythmic percussion. The instrumental base of Tango is therefore a trio made up of violin, piano and bandoneon.
The typical Tango orchestra designed originally by Julio de Caro in the 1920’s is a sextet with a piano, two bandoneons, two violins and one contrabass. The Tango orchestra follows the same line but adds more bandoneons, violas and violoncellos to the strings.