Importance of "Vadi" & "Samvadi" swaras in Hindustani Music

The "Vadi" & "Samvadi" Swaras are the most important Swaras in any raga. If the "Vadi" is in the "Poorvanga" of a raga, the "Samvadi" is in the "Uttaranga" of it & vice versa. These are so important that even if the Swaras of a Raga are the same, the mere change of these will create completely different ragas with different times of performance.

The classic example of this is the trio of Ragas Marwa, Puriya & Sohoni. All belong to "Marwa That" but drop the Pancham. Komal Rishabh & Dhaivat are the Vadi & Samvadi of Marwa which is an evening Raga. Gandhar &  Nishad are the Vadi & Samvadi of Puriya, which is also an evening raga. Tara Shadja &  Gandhar are the Vadi & Samvadi of Sohoni, which however is performed between 4 to 5.30 A. M. according to B. K. Roychaudhuri. (Dictionary of Hindustani Classical Music.) In addition, there are other differences in "Sancharas" these three ragas, which are beyond the scope of this essay, which only points out the importance of Vadi & Samvadi.

A clear idea of the three Ragas can be obtained by listening to recordings of Pandit Ravi Shankar's "Marwa", Ustad Vilayat Khan's "Puriya" & Pandit Nikhil Banerjee's "Sohoni."