Thaats (Hindustani Musical Scales)

 Thaats were created by a musicologist name Vishnu Narayan Bhatkhande (1860-1936) and his first ideas were inspired by the Mela System of Carnatic Music from South India.

Here are the 10 Thaats and some Ragas which belong to it.

1). Bilawal (Ionian mode): S R G M P D N S (no komal swar)

• Morning: Raag Alhaiya Bilawal, Raag Bilawal
• Evening: Raag Durga
• Night: Raag Bihag, Raag Hamsadhwani

2). Kalyan (Lydian mode): S R G M' P D N S (M' Teevra)

• Afternoon: Raag Shudh Sarang
• Evening: Raag Bhopali, Raag Meru Bihag, Raag Yaman
• Night: Raag Kedar 

3). Khamaj (Mixolydian mode): S R G M P D n S (n komal)

• Evening: Raag Desh, Raag Khamaj
• Night: Raag Gorakh Kalyan, Raag Champakali, Raag Jog, Raag Rageshree, Raag Saraswati, Raag Tilak Kamod

4). Bhairav (double harmonic): S r G M P d N S (rd-komal)

• Morning: Raag Ahir Bhairav, Raag Bairag, Raag Bhairav, Raag Jogiya, Raag Nat Bhairav, Raag Ramkali  

5). Kafi (Dorian mode): S R g M P D n S (gn Komal)

• Morning: Raag Asavari, Raag Jaunpuri
• Afternoon: Bhimpalasi
• Evening: Raag Kafi, Raag Patdeep
• Night: Raag Bageshree, Raag Chandrakauns, Raag Pilu, Raag Shivranjini

6). Asavari (Aeolian mode):  S R g M P d n - (gdn - komal)

• Morning Raag Asavari, Raag Jaunpuri
• Night: Raag Adana, Raag Darbari

7). Bhairavi (Phrygian mode): S r g M P d n S (rgdn- komal)

• Morning: Raag Bhairavi, Raag Komal Rishabh Asavari
• Night: Raag Malkauns

8). Poorvi - S r G M' P d N S (r M'd)  - rd - komal / M' Teevra)

• Dawn: Raag Lalit
• Afternoon: Raag Poorvi
• Evening: Raag Puriya Dhanashree 

9). Marwa - (Lydian b2) :  G M' P D N S (M' Teevra)

• Dawn: Raag Bhatiyar, Raag Sohini
• Evening: Raag Puriya Kalyan

10). Todi - S r g M' P d N S (rgM'd)

• Morning: Gujari Todi
• Afternoon: Raag Madhuvanti, Raag Multan

shrutis

The detailed study of the controversy regarding equality and in equality of shrutis in ancient, medieval and modern periods

Ancients who lived between the 4th century and 12th century believed that the interval between two shrutis was equal. This theory is called the Saman shruti antar. This was scientifically incorrect as science at that time was not developed. 

The medievals who were Lochana, Ahobala,Sri Nivas and Vyankathamukhi used the veena to locate the swaras. Because of this slightly advanced system of locating swaras on the stretched wire of veena, they realized that the interval between two shrutis is not equal.

 Therefore they did not accept the Saman Shruti antar of ancient writers like Bharata and Sarangadeva. Lochana, Ahobala and Srinivas lived between 15thC and 18th centuries and due to their advanced knowledge of shrutis , they found the interval between shrutis changed. 

Pandit Bhathkande the chief writer among moderns, lived in the 19th century. Thaats were created by a musicologist name Vishnu Narayan Bhatkhande (1860-1936) and his first ideas were inspired by the Mela System. During his time science had developed much and with the help of Acoustics or the science of sound , he discovered that the interval between shrutis was basically unequal and went further than the medievals and stated that even the location of komal Ri, komal Dha and Teewra Ma of medievals were wrong and placed the shudda swaras on the first shruti. His theory was correct as he used the modern major Diatonic scale or the Bilawal That as the proper shudda swar saptak.