Northern Indian Music has its own identity. This identity is preserved by its principles which serve as guides and borderlines for this style of music. Here we will go over these 35 principles in a comprehensive order. Actually there are 40 Principles, five have been removed as in my opinon , those offered no additional information. These principles will sum up almost everything that you have read so far.

1. Northern Indian music is based on ‘Bilable’ (same as standard major scale). The notes of Bilable Thaat are considered natural notes. Altering the natural state of notes in this Thaat makes all the other Thaats.
2. The melody section of northern Indian music is based on the Raag system. A Raag must contain minimum of ‘five’ to maximum of ‘seven’ (all) notes from an octave.
3. This way we can divide Raags into three categories:

a. Sumpooran (7 notes)
b. Chhadav (6 notes)
c. Audav (5 notes)

4. Nine (9) sub-categories are created by combining the main three categoriesas as described in this post and this post.
5. ‘Sa’ (first note or the keynote) cannot be excluded from any Raag.
6. ‘Ma’ (fourth) and ‘Pa’ (fifth) cannot be excluded from a Raag at the same time. If one is absent the other one must be present.
7. Every Raag must come from a Thaat and must have a ‘Vadi’ (dominant or the king) note, a ‘Sumvadi’ (sub-dominant) note, performing time, ‘Aroh –Avroh’ (ascending-descending) and pleasantness.

8. ‘Vadi’ and ‘Sumvadi’ notes are always on fourth or fifth place from each other. If the Vadi note is in the lower half of an octave (Poorvang), then the Sumvadi note must be in the upper half (Utrang).
9. The ‘Poorvang-Vadi’ (dominant note in the lower half) Raags show their characteristics in their ascending and ‘Utrang-Vadi’ (dominant note in the upper half) Raags show their characteristics in their descending.
10. Poorvang-Vadi or Utrang-Vadi Raags can be created from any Thaat. These Raags are also described as ‘Poorav Raags’ and ‘Utter Raags’ for short.
11. By Swapping the ‘Vadi’ and the ‘Sumvadi’ notes of any Raag, a new Raag can be created. This will also change a Raag’s performing time by 12 hours. That is because the ‘Poorvang-Vadi Raags’ are sung from noon to midnight and ‘Utrang-Vadi Raags’ are sung from midnight to noon.
12. ‘Sa’, ‘Ma’ and ‘Pa’ (first, fourth and fifth) are considered present in both ‘Poorvang’ (lower half) and ‘Utrang’ (upper half) (see this post for more details). If a Raag can be performed at any time, then one of these notes must be its ‘Vadi’ note.
13. Every Raag has a main note (Vadi Suwar). Normally it is not the keynote, but it is the most dominant note in the composition and a Raag can be categorized based on its ‘Vadi’ note.
14. Every Raag has a ‘Vivadi suwar’ (the enemy note). It can be used if the use doesn’t break the flow of a Raag.
15. Raags are divided into three categories based on the ‘Time Theory’.

a. Raags with Komal ‘Re’, ‘Dha’ (flat 2nd and 6th): These Raags are also called ‘Sandhi-prakash (twilight) Raags’ and are sung in the dusk and dawn hours. ‘Re’ and ‘Dha’ are always used in the morning ‘Sandhi-prakash Raags’ and ‘Ga’ and ‘Ni’ (3rd and 7th) are always used in the evening ‘Sandhi-prakash Raags’ regardless of their Jati (category) i.e. Sumpooran, Chhadav or Audav (hepta, hexa or hepta-tonic).
b. Raags with Shudh (natural) ‘Re’, and ‘Dha’ (2nd and 6th).
c. Raags with Komal ‘Ga’, ‘Ni’ (3rd and 7th flat).

16. Raags with Komal ‘Re’ and ‘Dha’ (second and sixth flat) are best for peaceful and sadness subject matters. Raags with Natural ‘Re’ and ‘Dha’ are used for eroticism and humorous subject matter and the Raags with Komal ‘Ga’ and ‘Ni’ (flat 3rd and 7th) are used for heroic and fearful subjects.
17. ‘N (lower)SR(komal)G’, this phrase quickly shows that a Raag is from ‘Sandhi-prakash’ (twilight) time category.
18. The fourth note of an octave (Ma), is considered a very important note. It is the only note, which can go sharp (Tivar) in Northern Indian music, and it defines a Raags time by day (Shudh or natural ‘Ma’) and night (Tivar or sharp ‘Ma’).
19. Tivar ‘Ma’ (sharp fourth) stays totally absent from the daytime Raags.
20. The Raags with Komal Ga, and Ni (flat 3rd and 7th) are performed in the noon or the mid-night.
21. After the Sandhi-prakash (twilight) Raags, the Raags with Shudh (natural) ‘Re’, ‘Ma’, ‘Dha’ and ‘Ni’ are performed.
22. ‘Sa’, ‘Ma’ and ‘Pa’ play a very important role in the Raags which are performed between 1-4 a.m. and p.m. These notes start to get stronger in the afternoon and after midnight Raags.

23. Raags Sound the best at their appropriate time (nowadays this rule is often ignored on stages and recordings).
24. A Komal ‘Ni’ (flat 7th) is seldom used in a Raag if the fourth is sharp (Tivar Ma).
25. The Raags, which have both ‘Ms’ (sharp and natural fourth), do sound a little bit similar to each other. Mostly their ascendings are different but the ‘Antras’ (verses) sound very alike. Special attention should be paid to keep these Raags pure.
26. A Suwar cannot be used in a row in its both conditions. For example if a Raag uses both ‘Ga’ (Komal and Shudh or 3rd natural and flat), both of these notes cannot be used in a row as ‘R-G(komal)-G-M’ (if ‘Sa’ is on ‘C’ then this means that you cannot go D-bE-E-F).
27. The Raags with both ‘Ma’ (natural and sharp fourth) which are performed between 7-10 p.m., follow this rule: Natural ‘Ma’ is used both ways (ascending and descending) but the sharp ‘Ma’ is only used in the ascending.
28. Another rule for the Raags between 7-10 p.m. is that ‘Ni’ (seventh) is mostly ‘Vakar’ in the ascending and ‘Ga’ is ‘Vakar’ in the descending. The ‘Ni’ (7th) is often a very weak note in these Raags. The word ‘Vakar’ simply means that the note is not used in a row. If you skip a note going up and then come back to it from the next note, that is called being ‘Vakar’ in the Ascending. For example, ‘E’ is ‘Vakar’ in ascending in this example:

C-D-F-E-G
And E is ‘Vakar’ in descending in this example:
G-F-D-E-C

29. Northern Indian music gives more importance to Raag (melody) rather than Taal (rhythm).
30. Raags with serious nature mostly stay in the lower octave and ‘Sa’, ‘Ma’ and ‘Pa’ play a very big role in these Raags. Usually one of these notes is Vadi in these Raags. That also means that if one of these notes is the Vadi note, that Raag probably is serious in nature.

31. A ‘Parmail-Parveshak Raag’ is performed to change Thaats. ‘Parmail-Parveshak Raags’ belong to more than one category and they make the change from one category to the other a gradual one.
32. The Shudh ‘Ni’ (natural seventh) is often used in the ascending in the Raags with Komal ‘Ni’ (seventh flat).
33. Notes in every Raag are used according to their strength in that Raag. Every note has More, equal or less power than others. The weak notes are not used much or they are used in certain phrases only. A weak note does not necessarily mean that it is Verjit (forbidden) in that Raag.
34. Raags, which are sung around noon, ‘Re’ or ‘Dha’ are not used in their ascending and if they are, they are very weak. But the Raags performed right on noon have very strong ‘Re’ and ‘Dha’ in them.
35. The seven notes used in the northern music are:

a. Chhadaj (shadaj)
b. Rishav
c. Gandhar
d. Madhyam
e. Puncham
f. Dhaivat
g. Nishad
These notes are shortened for singing and writing purposes. When singing or writing, these notes are pronounced (in short) as follows:
a. Chhadaj is pronounced ‘Sa’ and is written as ‘S’
b. Rishav is pronounced ‘Re’ and is written as ‘R’
c. Gandhar is pronounced ‘Ga’ and is written as ‘G’
d. Madhyam is pronounced ‘Ma’ and is written as ‘M’
e. Puncham is pronounced ‘Pa’ and is written as ‘P’
f. Dhaivat is pronounced ‘Dha’ and is written as ‘D’
g. Nishad is pronounced ‘Ni’ and is written as ‘N’

Once again the seven notes are
Sa, Re, Ga, Ma, Pa, Dha, Ni
And in this blog are written as above or as:
‘S, R, G, M, P, D, N.’

So wherever you see a letter representing a note, pronounce it as it is supposed to be rather than saying that letter’s name. This will make your learning process easier and you will get familiar with sounds and look of Indian music. Also, if a note is under lined that means it is Komal (flat) and if ‘M’ (Ma or fourth) has a standing line on it, that means it is Tivar (Sharp). Refer to ‘The Indian Notation System‘ post for more information on this subject.