Introduction to Indian Classical Music -7

Thât-The Parent Scale

Smt Tania Banerjee

[Mrs Tania Banerjee has been contributing excellent and informative articles on Indian classical music. In this ongoing series,

she writes about Thât this month. Please don’t miss this series.]

A Thât is a “Parent scale” in North Indian or Hindustani music. The concept of thât is not exactly equivalent to the Western musical scale because the primary function of a Thât is not as a tool for music composition, but rather as a basis for classification of râgas. There is not necessarily strict compliance between a râga and its parent Thât; a raga, said to ‘belong’ to a certain Thât need not allow all the notes of the Thât, and might allow other notes. Thâts are generally accepted to be heptatonic by definition.

The term Thât is also used to refer to the frets of stringed instruments like the sitar and the veenâ. It is also used to denote the posture adopted by a Kathak dancer (Classical Indian Dance Form) at the beginning of his or her performance.

The modern Thât system was created by Vishnu Narayan Bhatkhande (1860–1936), an influential musicologist in the field of classical music in the early decades of the twentieth century.


According to Vishnu Narayan Bhatkhande, each one of the several traditional ragas is based on, or is a variation of, ten basic Thâts, or musical scales or frameworks. The ten Thâts are Bilawal, Kalyan, Khamaj, Bhairav, Poorvi, Marwa, Kafi, Asavari, Bhairavi and Todi; if one were to pick a râga at random, it should be possible to find that it is based on one or the other of these Thâts. For instance, the Râgas Shree and Puriya Dhanashri are based on the Poorvi Thât, Malkauns on the Bhairavi, and Darbari Kanada on the Asavari Thât. It is important to point out that Bhatkande’s Thât-râga theory is hardly infallible, but it is nevertheless an important classificatory device with which to order, and make sense of, a bewildering array of râgas; and it is also a useful tool in the dissemination of the music to students.

It is worth noting that almost all the Thâts mentioned above are also râgas; and yet a Thât is a very different musical entity from a râga, and in this difference may lie, crucially, a definition of what a râga is or is not. A Thât is a musical scale, conceived of as a Western musical scale might be, with the seven notes presented in their order of ascent (arohana). For instance, Asâvari is presented, and notated, as Sa Re Ga (flat or komal) Ma Pa Dha (flat) Ni (flat) in ascent, or arohan. This is, however, only the skeletal musical structure of the Râga Asavari, an abstraction that is to be found nowhere but on the printed page or inside a textbook; the Râga  Asavari, in reality, and in exposition, is a very different thing. It goes straight from Re to Ma, and comes down to touch Ga, as it ascends; having touched Ni later, it returns to Pa, and, touching the upper Sa, returns to Dha and Pa again and again. Arohan and avarohan are, thus, inextricably and inseparably intermingled in the structure of this Râga . The Râga , then, is not a musical scale in the Western sense; it is a characteristic arrangement or progression of notes whose full potential and complexity can be realized only in exposition, and not upon the printed page. A condensed version of this characteristic arrangement of notes, peculiar to each Râga , may be called the pakad, by which a listener hears the phrase Sa Re Ga Ma Pa Ga, none of these notes being flat or sharp. Repeated in a recital, they will know that they are listening to the Râga  Gaud Sarang.

Two Râgas may have identical notes and yet be very different Râgas; for example, two Râga s mentioned earlier, Shree and Puriya Dhanashri, have exactly the same notes, but are unmistakably different in structure and temperament. The first can be identified by its continual exploration of the relationship of the note Re to the note Paa; while the repetition of the phrase Ma Re Ga Re Ma Ga, a phrase that would be inadmissible in the first Râga , is an enduring feature of the latter. Certain arrangements of notes, then, are opposite to particular Râga s and taboo to all others. A simple and abstract knowledge, thus of the notes of a Râga  or the Thât on which it is based, is hardly enough to ensure a true familiarity or engagement with the Râga , although it may serve as a convenient starting point. Thât familiarity can only come from a constant exposure to, and critical engagement, with Râga ‘s exposition.

In Bhatkhande’s system, the basic mode of reference is that which is equivalent to the Western Ionian mode or major scale (called Bilawal Thât in Hindustani music, Dheerasankarabharanam in Carnatic). The flattening or sharpening of pitches always occurs with reference to the interval pattern in Bilawal Thât. Each Thât contains a different combination of altered (vikrt) and natural (shuddha) notes with respect to the Bilawal Thât. In any seven-tone scale (starting with S), R, G, D, and N can be natural (shuddha, lit. “pure”) or flat (komal, lit. “soft”) but never sharp, whereas the M can be natural or sharp (tivra, lit. “fast”) but never flat, making twelve notes as in the Western chromatic scale. The sharp or flat tones are called vikrt swara (vikrt, lit. “altered”). Selecting seven tones in ascending order, where S and P are always natural whereas five other tones (R, G, M, D, N) can assume only one of its two possible forms, results in 32 possible modes which are known as Thâts. Out of these thirty-two possibilities, Bhatkhande chose to highlight only ten Thâts prominent in his days.

In effect only heptatonic scales are called Thâts. Bhatkhande applied the term Thâts only to scales that fulfil the following rules:

A Thât must have seven tones out of the twelve tones [seven natural, four flat (Re, Ga, Dha, Ni), one sharp (Ma)]

The tones must be in ascending sequence: Sa Re Ga Ma Pa Dha Ni

A Thât cannot contain both the natural and altered versions of a note

A Thât, unlike a Râga , does not have separate ascending and descending lines

A Thât has no emotional quality (which Râgas, by definition, do have)

Thâts are not sung but the Râga s produced from the Thâts are sung

One can arbitrarily designate any pitch as Sa (the tonic) and build the series from there. While all Thâts contain seven notes, many Râga s (of the audav and shadav type) contain fewer than seven and some use more. A Râga  need not to use every tone in a given Thât; the assignment is made according to whatever notes the Râga  does contain . The relatively small number of Thâts reflects Bhatkhande’s compromise between accuracy and efficiency: the degree of fit between a Râga  and its Thât is balanced with the desire to keep the number of basic Thâts small. Ambiguities inevitably arise. For example, Râga  Hindol, assigned to Kalyan Thât, uses the notes S G M D N, which are also found in Marwa Thât. Jaijaiwanti contains both shuddha Ni and komal Ni (and sometimes both versions of Ga as well), which by definition corresponds to no Thât. Bhatkande resolved such cases “by an ad hoc consideration, appealing to musical performance practice”

Note that Thâts only give a rough structure of the Râga and do not give an idea of how the Râga  should be sung. It is pakad of the Râga  that gives the chalan or way of singing of the Râga .

Râga  that don’t fall in Thât system

There are many Râga s that don’t fall in Thât system. Some Râga s have been derived from Carnatic Music and hence do not fall under Hindustani Classical Thât System. Some of them are- 1. Kirvani 2. Nat Bhairav 3. Charukeshi 4. Madhuvanti.




is a musician and a student of the science of music. She has been introducing the inticracies of classical music to Vedanta Vani readers.

Abhishek Chakraborti

is the Contributing Editor of the Music Page

Abhishek lives in Holland and is an excellent musician. He is also devoted to the ideals of Sri Ramakrishna, Mother and Swamiji.