Nishada (Sanskrit: निषाद, romanized: Niṣāda) is the seventh and last svara in Hindustani music and Carnatic music.
[1][2] Nishada is the long form of the syllable नी.
[3] For simplicity in pronouncing while singing the syllable, Nishada is pronounced as Ni (notation - N).
The following is the information about Nishada and its importance in Indian classical music : So the svara Ni is formed from Shadja.
Consequently, the Ni after the Dha of 900 Hz (Taar Saptak) has a frequency of 800 Hz i.e. the double of the Lower octave Ni.