Thaat Classification System in Hindustani Music
“Naad se swara, swara se saptak, saptak se thaat”
The ‘thaat’ system in Hindustani music was created as a way to classify the countless ragas that exist within the style. It takes ragas with similar features and groups them together.
A ‘thaat,’ also called a family, is essentially a set of ascending notes from which ragas are derived. It is considered to be the parent scale, similar to the Western musical concept of a mode. However, while modes are meant to be sung and played, thaats are only used as a way to classify ragas together.
This classification system was introduced originally in Carnatic music by the musicologist, Pt. Venkatmakhi, who created 72 melakartas, or groups, in which ragas could be classified.
Taking this as inspiration, a musicologist by the name of Pt. Vishnu Narayan Bhatkhande (Chatur Pandit) established the thaat system in the 20th century as the way to classify ragas in Hindustani music.
Pt. Bhatkhande’s system took 10 different combinations of the 12 swaras and established them as ‘thaats. He named each thaat after 10 main ragas of that time who shared an acending scale with the thaat. These 10 ragas are now known as the Ashraya Ragas or Janaka Ragas of their respective thaats. Per Pt. Bhatkhande, all other ragas in the same family are variations of the Janaka Raga.
A thaat, though named after a raga, is not the same as a raga. A thaat must follow the following rules:
A thaat must have 7 out of the 12 swaras used in Hindustani music
A thaat can only consist of an Aaroha, or ascending scale
A thaat cannot have 2 versions of the same note i.e komal ni and shuddha ni; it can only use one of the two
A thaat has no emotional quality (which ragas, by definition, do have)
Thaats are not sung but the ragas produced from the thaats are sung
The 10 thaats outlined by Pt. Bhatkhande are as follows:
Kalyan: S R G m P D N S’
Bilawal: S R G M P D N S’
Khamaj: S R G M P D N S’
Bhairav: S R G M P D N S’
Poorvi: S R G m P D N S’
Marwa: S R G m P D N S’
Kafi: S R G M P D N S’
Asavari: S R G M P D N S’
Bhairavi: S R G M P D N S’
Todi: S R G m P D N S’
*All underlined notes denote a komal, or flat note. A lower case letter denotes a teevra, or sharp note*
Sources:
Sangeetanjali (Part 6) by Pt. Omkarnath Thakur
Sangeet Visharad by Vasant
