Also spelled: Carnatac, Karnatic.
The traditional music of South India. It has a rich and interesting history, which will not be given here. The other form of 'classical music' (as opposed to the modern 'light music') practiced in India is Hindustani music. This writeup focuses mainly on its vocal forms, which most people consider to be the most important.
The basic concept of Carnatic music is the raaga which is somewhat analogous to the Western scale, but not precisely. I have heard that it is closer to a 'mode', but not knowing what a mode is, I cannot verify the accuracy of this claim. The raaga's ascending scale (Arohana) may be different from its descending scale (Avarohana).
There are eight possible notes in a scale, as in Western music. These are: Sa, Re, Ga, Ma, Pa, Da, Ni. They are often abbreviated S, R, G, M, P, D, N, S. (In case you're curious, the notes are abbreviations for the Sanskrit names Shadjam, Rishabham, Gandharam, Madhyamam, Panchamam, Dhaivatam and Nishadam. If you're really curious, /msg me to find out how they're pronounced, since I'm not using a completely phonetic transcription.)
There are 72 main raagas, known as the Melakartha raagas. These are each given a number and arranged in order. It is possible to find the number of a raaga from its name using the Katapayadi Sutra. However, there are many more than 72 raagas. Each Melakartha raagas has a set of raagas whose notes are the same. However, these 'subset' raagas do lack some of the notes of their 'parent'. To illustrate:
Raaga A: S R1 G2 M1 P D1 N2
Raaga B: S R1 M1 P D1
(kudos to anyone who can recognise these raagas)
Note that there are no numbers next to S and P. These notes are chosen before each peice according to the preference of the musician. Unlike Western music, in which a note is specified in relation to a fixed middle C, Carnatic music notes are specified in relation to notes chosen by the musician.
The student of vocal Carnatic music (unlike Hindustani students -- this is a major difference between the two systems) goes through several levels in their training. However, this system can be modified at the discretion of the teacher:
Swaravali Varisaigal
Jantai Varisaigal
Dhattu Varisaigal
Upper Sthayi Varisaigal
Madhya Sthayi Varisaigal
Alankaras
Geethas
Swarajathis
Jathiswaras
Varnams
Keerthanas
These are arranged in an order that is supposed to be easy for the student. A Varisaigal means that the peices in that level follow regular patterns. (Such as S R G M, R G M P, G M P D, M P D N, etc.) The Swaravali Varisaigal is meant to teach how to sing (i.e., the basic concepts). The Jantai Varisaigal are meant to improve skill in singing quickly and accurately. The Dhattu Varisaigal are meant to teach the student to keep track of the scale, so as not to sing out of tune. The next two, the Sthayis, have no real purpose as far as I can tell. The Alankaras are the first peices that do not follow a repeating pattern. The Geethas are the first peices that have words. The Swarajathis and Jathiswaras, unlike the previous levels, include different tempos. And finally, the Varnams and Keerthanas are proffesional-level peices (the kind that are sung in concerts).
Finally, the beat is kept using a system called a thala. The musician strikes her/his hand on her/his thigh in various ways. For example, a possible thala (for illustration purposes only -- there is no such thala in real life) is striking the thigh with palm down, then with palm up. These strikes (known as angas each have names:
Anudhrutam (flat palm, face down)
Dhrutam (Anudhrutam, then a strike with the palm facing up
Laghu (One Anudhrutam, then a tap of the pinky, ring finger and middle finger, in that order)
(The other angas are rarely used and will not be covered)
These angas are combined in different orders to form the Saptha Thalas, or seven main thalas.
Several Carnatic music concerts are performed in the US. To see one, check your paper -- there's probably an ad. Also, check out http://www.southindiafinearts.org/ for upcoming SIFA concerts. For more information, buy the Carnatic music instruction book Ganamrutha Bodhini by A.S. Panchapakesa Iyer. It includes a few sections devoted to theory as well as other instruction.