Bill D, I think you may be confusing the bandoneon with the chemnitzer, a similar, but not quite the same, keyboard or sound. The bandoneon usually only has 2 sets of reeds tuned an octave apart, whereas the chemnitzer normally has 3 or 4 sets. It is the latter which is played predominantly in the mid west of the USA amongst Eastern European migrants and their descendents.

MC

By the way, apologies to any purists/pedants; I know there is an accent over the last letter e of bandoneon, but my computer refuses to comply!