As a young and upcoming musician in the late eighties I have for long heard experts talk about ragas being classified as 'scale' ragas and 'rakti' ragas. The rakti ragas were supposed to be more classical and aesthetic and provided a better listening experience to the connoisseur. There was always the dismissal of the scale ragas as being a mere collection of notes that lacked any innate aesthetics and that raga elaborations invariably 'descended' to an intellectual exercise of playing on the notes. This argument continues and musicians and rasikas have very strong view points on this matter.
A historical analysis of the evolution of ragas will clearly show that there are ragas that were born out of melodies whilst others that were born out of scales. A melody is just a collection of notes that one gets to hear. For instance a classic case is the raga Neelambari that traditionally owes its roots to the folk tradition. Neelambari has been associated with 'Taalaattu' or the song that puts children to sleep. Different variants of the lullaby generally conformed to a melody that became Neelambari. Similarly academics have traced the origin of ragas like Anandabhairavi and Huseni also to the folk versions and their interpretations. There is also strong evidence to suggest that the ancient tamizh music with their 'panns' influenced the evolution of ragas atleast in South India. Subsequent research of the traditional temple music and its singing by the 'odhuvars' lends credence to some of this. Before we jump to any conclusion we have to understand that all this has happened over a fairly long period and much of the evolution process has not been exactly documented for us to comprehend it completely. So what we have today is a collection of the so called 'rakti' ragas or those that have an inherent aesthetic to them as a result of continuous singing and polishing that has happened over so many years.
In the modern day, a 100 year analysis of raga evolution can show us how much change has happened to the nature and scale of ragas. Ragas have a capacity to slowly evolve and change over time because of the way musicians handle them and explore them. A classic parallel to this is the evolution of colours in the spectrum. How today a computer can generate millions of colours that change the way we look at art as compared to the traditional usage of the same. Can scales acquire 'rakti' or can musicians over a period of time polish and shape a raga to such an extent that the listener feels that he can experience an innate aesthetic beauty in the raga. This is really the point of the proponents of innovation. My guru Shri KSK believed very strongly that ragas evolve and acquire 'rakti' with time. He gave us the classic example of a raga like Charukesi. A reasonably modern raga, it became popular after the success of some film melodies like Aadal kaaneero, Manmada leelayai and Vasantha mullaippole vanthu. Afterall the most popular kriti in Charukesi was Adamodi and it became well known mostly through Madurai Mani Iyer. Musicians senior to MMI like Maharajapuram, Ariyakudi and Musiri hardly sang Charukesi. This raga by the seventies had gained so many different colours in the usage. There was a lighter version, an intellectual scalar version and of course a 'rakti' version if one might call it that. The bottom line is that today Charukesi is a beautiful raga that has also been borrowed by Hindustani musicians. (There is a commercial release of a Charukesi by Ustad Amir Khan)
Now let us look at some of the ragas that came into vogue after Tyagaraja or to be more specific those that Tyagaraja composed in. Compared to some older ragas these are quite modern. There is the argument that it was first handled by a musical genius, but then the same music genius' handling of several ragas have been dismissed as scalar. Let us consider two ragas like Jayantasena and Nalinakanti. The former is a typical rakti raga in the eyes of many while the latter belongs to the 'dismissed as scalar' category. Both ragas have become known through the two Tyagaraja pieces Vinata suta and Manavyala kinchara. Vinata suta became popular after it was taken and polished by Kancheepuram Naina Pillai. Since then the song has a basically common structure that most musicians stick to in their renditions. Manavyala on the other hand has been exploited by all and sundry and has gained the status of Charukesi in the modern time. The GNB and Sankara Iyer compositions in Nalinakanti give it the intellectual and rakti colours respectively, while Manavyala changes colour according to the artiste.
Being the young upstart music student that I was in the eighties, I have had long arguments with my Guru. In order to show how much rakti meant to him he said "Do you know I prefer Sourashtram to Chakravakam." This was a man who had composed his first tune in Gopikatilakam, a 'not exploited scale' in the early forties. So much for rakti! He then proceeded to tell me how any raga is only a collection of notes and the beauty comes from the handling. He said, "I'd rather listen to a satisfying Ranjani than a badly sung Sahana." But then I have heard some 'knowledgeable' rasikas (like our own Mr Srinivasan) tell me that they'd rather hear (or even read) about a Begada (even if sung badly) than a brilliantly sung Dharmavati! Finally it is a matter of taste and things boil down to individual likes and dislikes. It is however interesting to see how people like to justify their likes by adding phrases like rakthi or classical.