Graha bhedam

Graha Bhedam in Carnatic music is the process (or result of the process) of shifting the Tonic note (śruti) to another note in the rāgam and arriving at a different rāgam.

Graha literally means position and Bhedam means change. Since the position of the śruti is changed (pitch of the drone), it is also sometimes called Swara Bhedam or Śruti Bhedam though Śruti Bhedam and Graha Bhedam have some technical differences.

Modal shift of the Tonic note to higher notes of a rāgam, while retaining the note's positions (swara sthānas – sthāna means position/ pitch), results in different rāgams. This is called Graha Bhedam.

A simple practical demonstration of Graha Bhedam can be taken up by playing the structure of a rāgam with the drone set to Sa (Shadjamam). Then if we keep playing the same keys/ notes, while shifting the drone to another note in the rāgam, to form the new śruti/ tonic note, the result is a different rāgam.

When Graha bhedam is applied on Shankarabharanam's notes, it yields 5 other major Melakarta rāgams, namely, Kalyani, Hanumatodi, Natabhairavi, Kharaharapriya and Harikambhoji.

Notes on above table

Graha Bhedam can be applied on most Melakarta rāgams to yield other Melakarta rāgams (16 of the 72 do not yield any valid Melakarta scale). When applying such modal shift of tonic note, some results are not valid Melakarta rāgams (rules of the definition of Melakarta are violated). Example scenarios are missing Panchamam (Pa) or two of particular note (Rishabham (Ri), Gandharam (Ga), Madhyamam (Ma), Dhaivatam (Da) or Nishadam (Ni)).

See Example Illustration in previous section.

The Graha Bhedam derivative of Kanakangi is Kamavardhini and vice versa.

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Wikipedia