analysis-1
In the 72 melakarta scheme, there are 40 vivadi melas and 32 non-vivadi melas.
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Even during the TRINITY'S time, there was a
ban on vivadi scales.
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There are thus 16 non-vivadi scales in M1 group and another 16 non-vivadi scales
in M2 group.
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The advantage in using non-vivadi scales is that the swarams are very easy to note exactly as in HM.
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S R1 R2 G1 G2 M1 M2 P D1 D2 N1 N2 S'
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So, there is no necessity for things like r3, g3, d3 and n3
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The approved scales then are
M1 set
8,9,10,11
14,15,16,17
20,21,22,23
26,27,28,29
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M2 set
44,45,46,47
50,51,52,53
56,57,58,59
62,63,64,65
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Thyagaraja Swami used about 55 scales and all of them were non-vivadi
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He composed one or two critis only in some ragas and they are known as rare ragas.
But even there, these rare ragas are janyams of non-vivadi scales!
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