थाट — Bhatkhande's ten parent scales

Pandit Vishnu Narayan Bhatkhande (1860–1936) classified the ragas of Hindustani music under ten थाट, set out in his Hindustani Sangeet Paddhati. A थाट is a classification, not a performance: it has exactly seven swaras, is written only in आरोह, and is never sung as a raga itself.

Why 32 are possible and only 10 were chosen: सा and प are fixed; रे, ग, ध and नि each take a शुद्ध or कोमल form, and म a शुद्ध or तीव्र form — so 2 × 2 × 2 × 2 × 2 = 32 scales are theoretically available. Bhatkhande selected the ten that actually account for the ragas in practice.

The 72 मेलकर्ता — the Carnatic answer to the same question

The Carnatic system classifies its ragas by मेलकर्ता (parent scale), and it counts 72. The scheme is credited to Venkatamakhin, who set it out in the Chaturdandi Prakashika (seventeenth century); the names and order in use today were later regularised by Govindacharya.

Why 72 and not 32: the Carnatic system allows more forms of रे-ग and ध-नि than the Hindustani one — in effect six usable combinations for each pair — and two forms of म:

• ›6 (रे-ग combinations) × 6 (ध-नि combinations) × 2 (म) = 72
• ›The first 36 मेलकर्ता take शुद्ध म; the second 36 take प्रति म (the Hindustani तीव्र म)

The two systems side by side

The contrast is the point a paper tests: Bhatkhande's list is descriptive (the scales ragas actually use), Venkatamakhin's is generative (every scale the rules permit).

What makes a raga a raga — राग लक्षण

The minimum rules

• ›At least five swaras — a raga may not have fewer
• ›सा is never omitted
• ›म and प are never omitted together — a raga may drop one, not both
• ›It must have रंजकता — the power to colour the mind; a scale that is merely correct is not yet a raga

जाति — by the number of swaras

• ›औडव — 5 swaras · षाडव — 6 · सम्पूर्ण — 7
• ›आरोह and अवरोह are counted separately, so 9 जातियाँ result (औडव-औडव, औडव-षाडव … सम्पूर्ण-सम्पूर्ण)

The swaras by their role

• ›वादी — the most prominent swara, called the king of the raga
• ›संवादी — the second most prominent, the minister, usually a fourth or fifth from the वादी
• ›अनुवादी — the other swaras used, the servants
• ›विवादी — a swara foreign to the raga, the enemy; touched only rarely and deliberately, for colour

पकड़ is the short phrase by which a raga is recognised; चलन is the way it characteristically moves.

Time theory, and the ragas every source agrees on

समय सिद्धांत — ragas are assigned to times of day, and the वादी decides which half:

• ›पूर्वांग वादी (वादी in सा–म–प, the lower half) — sung from noon to midnight
• ›उत्तरांग वादी (वादी in म–प–सां, the upper half) — sung from midnight to noon
• ›संधिप्रकाश राग — the twilight ragas of dawn and dusk, typically with रे and ध कोमल: भैरव at dawn, पूर्वी and मारवा at dusk

Ragas whose facts do not vary between authorities

आश्रय राग is the raga that gives a थाट its name — यमन for कल्याण, भैरव for भैरव, भैरवी for भैरवी.

Points to Remember

• ›Bhatkhande: 10 थाट — बिलावल, खमाज, काफी, आसावरी, भैरवी, भैरव, कल्याण, मारवा, पूर्वी, तोड़ी
• ›A थाट has exactly 7 swaras, only आरोह, and is never sung as a raga
• ›32 थाट are theoretically possible (2⁵); Bhatkhande chose the 10 in use
• ›72 मेलकर्ता — Venkatamakhin, Chaturdandi Prakashika; 6 × 6 × 2
• ›A raga needs 5+ swaras; सा never omitted; म and प never omitted together
• ›जाति: औडव 5 · षाडव 6 · सम्पूर्ण 7 → 9 जातियाँ across आरोह-अवरोह
• ›वादी king · संवादी minister · अनुवादी servant · विवादी enemy
• ›पूर्वांग वादी → noon to midnight · उत्तरांग वादी → midnight to noon
• ›यमन कल्याण थाट, वादी ग · मालकौंस रे-प वर्जित · भूपाली म-नि वर्जित
• ›Exam tip: a question on a raga's thaat is usually a question about its altered swaras — work from the तीव्र म or the कोमल रे, not from memory of the name