Authors: Kaushik Banerjee, Anirban Patranabis, Ranjan Sengupta, Dipak Ghosh
Title: "How Harmonium Accompanimente in Hindustani Music Is Changing the Scale System"

It was middle of 19th century when French-made hand-pumped Harmonium stepped into the arena of Indian music by some missionaries. Apart from the historical evidence it had been a great impact on the basic Hindustani musical genre; Especially on Hindustani vocal music. And within next fifty years it would have been a foremost accompanying musical instrument of Hindustani classical vocal music. In this paper we attempted to find out the influence of harmonium usage in equally tempered scale (ET scale) on the raga renderings in Hindustani music. The pitch period was extracted from 17 renderings of 12 eminent vocalists of Hindustani music, for two different ragas. Only the steady pitch periods were used for analysis. The approach was to study the distribution of steady pitch states against the ratio of each note in an octave. Prominent peaks indicate preferred ratios. Attempt was made to see whether these ratios obey ET scale or Indian 22 sruti intervals. The result shows that most of the vocalists follow a mixture of both systems with a preference of any one depending on the raga.