Hamsadhwani

Hamsadhvani (meaning Sound of Swans) also spelled as Hansadhwani, is a rāga in Carnatic music (musical scale of Carnatic tradition of Indian classical music). It is an audava rāgam (or owdava rāga, meaning pentatonic scale). It is a janya rāga of the Melakartha raga, Dheerasankarabharanam (29th) but according to Hamsadhvani's prayoga or the way it is sung it is said to be the janya of Kalyani (65th) Hamsadhvani is also extensively used in Hindustani music and said to be borrowed into it from Carnatic music. It was created by the Carnatic composer Ramaswami Dikshitar (1735–1817) and brought into Hindustani music by Ustad Aman Ali Khan of the Bhendibazaar gharana.

Hamsadhvani does not contain madhyamam or dhaivatam. It is a pentatonic scale (audava-audava ragam in Carnatic music classification – audava meaning 'of 5'). Its ārohaṇa-avarohaṇa structure (ascending and descending scale) is as follows (see swaras in Carnatic music for details on below notation and terms):

The notes used in this scale are shadjam, chatushruti rishabham, antara gandharam, panchamam and kakali nishadam. . In Hindustani music it is associated with Bilaval thaat (equivalent of Shankarabharanam).

Hamsadhvani rāgam lends itself for elaboration and exploration and has many compositions in both classical music and film music. It is usually sung at the beginning of a performance. There are many kritis (compositions) in praise of Lord Ganesha set in this musical scale.

Hamsadhvani's notes when shifted using Graha bhedam, yields another pentatonic rāgam, Nagasvaravali. Graha bhedam is the step taken in keeping the relative note frequencies same, while shifting the shadjam to the next note in the rāgam. For more details and illustration of this concept refer Graha bhedam on Hamsadhvani.

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