The Khamak is a string instrument similar to the Gubguba or Anandalahari, originating in bengal region, common in folk music of Bengal, Odisha and North East India, especially Baulgaan.
The only difference from ektara is that no bamboo is used to stretch the string, which is held by one hand, while being plucked by another.
[1] In Anandalahari, the other end of the string is fixed inside a copper pot only.
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