Dvoyanka

The Bulgarian dvoyanka is a double flute made of a single piece of wood, with six sound holes on one side. It is most frequently made of ash-wood, plum tree, pear tree, cornel or boxwood. The tune is played on the right pipe, while the left pipe provides a flat tone (or drone) as accompaniment. The playing structure on the right pipe is similar to...
Found on http://en.wikipedia.org/wiki/Dvoyanka

Dvoyanka

Bulgarian double fipple flute.
Found on http://www.hobgoblin-usa.com/info/glossary.htm
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