Dr. Parthasarathy Sriram
Ragas are sometimes defined as melody types. The raga system is a method of organizing tunes based on certain natural principles. Tunes in the same raga use the same (nominal) swaras in various combinations and with practice, the listener can pick up the similarity. Each raga has a swaroopam (a musical form or image) that is defined by the swaras used, the gamakas given to these swaras, the sequence in which the swaras occur etc. This definition is termed as the raga lakshanam. (The magazine Sruthi usually contains a discussion of ragalakshanam of one or two ragas in each issue). Raga lakshanam usually contains the arohanam, avarohanam, details of raga chaya swaras (the swaras which are chiefly responsible for the characteristic melody of the raga), gamakas, characteristic swara phrases and general usage notes. It is intended more for the performer than for the listener. We shall first define arohanam and avarohanam. Arohanam is the sequence of swaras used in a raga in the ascending passages i.e. as the pitch goes up. Avarohanam is the sequence of swaras to be used in descent. The arohanam and avarohanam (or the scale) of a raga provide only a skeletal outline upon which the rest of the raga is formed.
Ragas are not simply abstract collections of swaras that occur together to produce a tune. Each raga has a distinct image or swaroopam and it is this which defines a raga. Arbitrary selection of a set of swaras is unlikely to produce a distinct raga swaroopam and this is the reason for attributing the foundations of the raga system to nature. The ragas that we know of are the products of centuries of experimentation. Each ragam has associated with it a feeling that it induces in the listener and the performer. Hours of dedicated practice with a single raga (Saathakam) results in the realization of the raga swaroopa on the part of the performer and this is often referred to as obtaining a Dharshan of that particular raga. The unfortunate consequence of this is that various performers have slightly different mental concepts of a single raga and this is manifest in their music. But the good part is that it adds a tremendous variety to the music. This is also the reason why Carnatic music (performance) can never really be learnt from a book but needs a Guru who can portray the raga swaroopam in such a manner that the pupil can pick it up. From the viewpoint of the listener, a realization of the raga swaroopam means that some of the qualities of the music can be anticipated and this contributes greatly to listening pleasure.
Ragas fall into two types, the base or melakarta ragas and the derived or janya ragas. Melakarta ragas have a formal structure and follow a fairly rigid scheme of scientific organization whereas the janya ragas are rooted in usage and are liable to evolve with the music. In fact many janya ragas change their character over time. Janya ragas are derived from the melakarta ragas through various means as described subsequently. Melakarta ragas are identified by the fact that they use all seven swaras and the arohanam and avarohanam are always Sa-Ri-Ga-Ma-Pa-Da-Ni-Sa and Sa-Ni-Da-Pa-Ma-Ga-Ri-Sa. This type of arohanam and avarohanam is denoted by the term sampoornam, indicating completeness. The existence of multiple swara sthanas for Ri, Ga, Ma, Da and Ni implies that by collecting combinations of these, we can form a system of melakartas. This concept will be developed in the succeeding section. Any raga that does not belong to the melakarta system is a janya raga. Janya ragas are characterized by missing notes in the arohanam and/or avarohanam (eg. Sa-Ri-Ga-Pa-Da-Sa), the use of twisted progressions (eg. Sa-Ga-Ri-Ma-Pa-Da-Ni-Sa) etc. Janya ragas and their classifications will be described subsequently.
The definition of melakarta given above is a currently accepted one. In the past, melakartas have been defined in other ways, sometimes incompatible with the sampoornam characteristic. The present system is mathematically much more elegant and that appears to be one of the reasons for its wide spread acceptance and use in the past few centuries.