8 – Indian Music Systems – Scales
As said before, Indian systems (both Hindustani and Carnatic) use the 12-note system. However, the main difference between the two systems is that the Indian system uses a sliding octave scheme, while western music uses the absolute pitch octave. That is, in the Indian system, the tonic can be any note on the western octave, and the other notes are fixed relative to the tonic. So, if the tonic, Sa, is chosen as C4, then komal Ri and Ri are D4♭ and D4, komal Ga and Ga are E4♭ and E4, Ma and tivr Ma are F4 and F4#, Pa is G4, komal Dha and Dha are A4♭ and A4, komal Ni and Ni are B4♭ and B4, and the next Sa is C5. And if the tonic, Sa, is chosen as G4#, then komal Ri and Ri are A4 and A4#, komal Ga and Ga are B4 and C5, Ma and tivr Ma are C5# and D5, Pa is D5#, komal Dha and Dha are E5 and F5, komal Ni and Ni are F5# and G5, and the next Sa is G5#.
The tonic note to be chosen is left to the musician. Male singers normally use a note of the lower ranges (the first tetrachord of the western octave) of the 4th octave, while female singers use a note of the higher ranges (the second tetrachord).
So, Indian music sees no difference between a C major scale and a G# major scale. They are seen as the same scale starting on different tonics.
Note that even in western music, singers can transpose a piece of music from a scale employing one root note (tonic) to one employing another.
One thing to note here is that with equal temperament tuning, transposition to different tonics sounds smooth, while if just intonation is employed based on one tonic, transposing to other tonics may sound harsh. [Many Indian systems employ just intonation tuning for their instruments, and in this case, the tonic needs to be identified before tuning to get the best results.]
Hindustani systems and Carnatic systems create scales in different fashions. Let us first look at the Carnatic system.
Carnatic scales are called melakarta ragas. As is the western system, scales are normally heptatonic (of seven notes). When you choose seven notes from twelve, one key need is to avoid bunching all the notes on one side of the octave (like, say, the first seven notes). Western systems do this by ensuring two or three full tone interval gaps between the two semitone intervals. We saw this before.
Melakarta raga scales fix two notes as constant in all scales – the Sa and the Pa. All scales have these two notes. The next rule is that a scale will have either Ma or Ma#, never both. Thus, four notes are taken care of. Of the remaining eight notes, two are chosen from the Ri and Ga notes and two from Dha and Ni notes. Thus, you get seven spread out notes in a scale. See figure.
Let us create some of the scales. Let us choose, say, Ma as the variant of the Ma-Ma# combination.
Of the four notes in the first tetrachord, Ri♭, Ri, Ga♭ and Ga, we can chose combinations of two in six ways: Ri♭ and Ri; Ri♭ and Ga♭; Ri♭ and Ga; Ri and Ga♭; Ri and Ga; Ga♭ and Ga. Let us choose, say, Ri♭ and Ri. With this choice, we can have as the two other notes one of the following six combinations: Dha♭ & Dha, Dha♭ & Ni♭, Dha♭ & Ni, Dha & Ni♭, Dha & Ni, Ni♭ & Ni. Then still holding Ma, choose Ri♭ and Ga♭. With this combination also we can have six combinations of Dha and Ni.
We can thus have six combinations of Ri and Ga and with each one of these combinations have six combinations of Dha and Ni. Thus, totally we can have 6 x 6 = 36 such combinations.
Now, the same 36 combinations can be chosen with Ma# as the Ma variant. So totally we can have 36 x 2 = 72 combinations or scales. There are thus 72 melakarta ragas or scales. The same notes are used for both the ascending and descending variations of the scale.
There is an interesting scheme to name these scales. We will not go into details here.
Note here that some of these scales do have the interval scheme 2,2,1,2,2,2,1, thus creating the equivalent of the major (Ionian) scale. You can have all the scales we saw before in the western system in the Melakarta scales also.
[One thing to note here is the use of chromatic intervals. Scales can be formed using both variants of Ri, Ga, Dha and Ni. (That is, a scale can have both Ri and Ri♭, or Dha and Dha♭ etc.) This creates intervals of succeeding half tones, which may not be good.
Look at the figure. If we choose the scale Sa, Ri♭, Ri, Ma, Pa, Dha, Dha♭, Sa, we get intervals 1,1,3,2,1,1,3. And, if we choose the Ma# variant of this scale we get an even a two-tone interval: 1,1,4,1,1,1,3.
The Hindustani system tries to mitigate this by positing one more condition. That is, only one of the variants of a note is allowed. So, you cannot have both Ri and R♭, or both Dha and Dha♭. Other conditions remain the same. So, two combinations on the Ri-Ga side (Ri♭ and Ri; Ga♭ and Ga) and two on the Dha-Ni side (Dha♭ and Dha; Ni♭ and Ni) are eliminated. So, you get 4 combinations on one side and four on the other making for 4 x 4 x 2 = 32 scales. The Hindustani scales are called thaats. While the Hindustani system removes some of the issues with Melakarta system, you still have semitone intervals in a scale (like between Ri and Ga♭, M# and Pa and Dha and Ni♭).
As before many of these thaats can be mapped onto the western scales. For example, the Bilaawal thaat is the equivalent of the major (Ionian) scale.
All the scales in both the Hindustani system and the Carnatic system have specific names.
As we saw for the western scales, in Carnatic scales we can get different modes for the interval pattern, by shifting them right. For example, the scale with the interval we saw before, 1,1,3,2,1,1,3 (called Kanakangi scale) can be shifted one position to the right to get the pattern 1,3,2,1,1,3,1. This is called the Kamavardhini scale. This process of shifting the intervals is called graha bhedam in Carnatic music. Sometimes the shifted intervals map onto an illegal scale (where, say, Ma and Ma# both occur).
[Check out the paper The Rags of North Indian Music by NA Jairzabhoy]
Visit the following pages for notes on particular elements of music.