The most widely used percussion instrument in eastern India is the khol. It is also called mridang because it is made of clay, i.e., mrit or mud. The instrument is closely associated with the Vaishnavite music of Bengal and Assam.

The khol is a barrel-shaped asymmetrical drum. Its two faces are of different sizes, and it seems to resemble the ancient Gopuchha shape of drums, as described by Bharat in his Natya Shastra.

No instrument except khol and cymbals are found to have continuously been used to accompany Bargeets and Ankiya Geets.