What are Sruti or Shruti in Hindustani Classical Music: History Origin and Facts
What are Shruti/Sruti?

To understand what Sruti is, first you need to understand how the octaves are defined. When you sing the Saragam (Sa Re Ga Ma Pa Dha Ni SA), the first Sa and the second SA always have a relation in their frequencies, that is, the frequency of SA (the last note) is exactly double of that of the frequency of Sa (this first note). So, an Octave is actually the frequency band between Sa and SA.

Now considering the capabilities of human biology, human Ears cannot differentiate clearly between very small changes in the frequencies and hence to make a clear difference in the sounds, there must be a minimum difference between two sounds, and this is how Srutis are defined. Srutis divide the frequencies in an Octave into 22 distinct parts and each Sruti represents a relation between its previous Sruti and the next Sruti.

It is important to understand that Srutis represent a relation between the previous and next Sruti and hence no matter which frequency an Octave starts the Srutis are going to divide it into 22 relative parts.

Also, Srutis are not equidistant, which means two Srutis can have a variable frequency difference but the proportion in each octave is supposed to be same.

Here is the list of divisions of Srutis in Hindustani Classical Music.

Sa Re Ga Ma Pa Dha Ni
4 4 3 2 4 3 2

Here is a full list of all the Srutis and their Carnatic Music names.

Sruti Name ​Sign Carnatic Name
22 SHADJA TARA S Shadja Tara
21 Tivra Ni N+
20 SHUDDHA NI N Kakali Ni
19 Komal Ni n Kaisiki Ni
18 Ati Komal Ni n- 
17 SHUDDHA DHA D Chatuhasruti Dha 
16 Trisruti Dha D-
15 Komal Dha d SHUDDHA DHA
14 Atikomal Dha d
13 PANCHAMA P Pa
12 Tivratara Ma m+
11 Tivra Ma m Prati Ma
10 Ekasruti Ma M+
09 SHUDDHA MA M Shuddha Ma
08 Tivra Ga G+
07 SHUDDHA GA G Antara Ga
06 Komal Ga g Sadharana Ga
05 Atikomal Ga g-
04 SHUDDHA RI R Chatuhsri Ri
03 Madhya Ri R-
02 Komal Ri r Suddha Ri
01 Atikomal Ri r-
0 SHADJA S Shadja Madhya 
​ ​ ​

There is a significant similarity between Hindustani Classical Music and the ancient Greek Music culture. But a major difference between Indian and Greek musicology is that in Greece the Octave was divided into 24 Srutis so the proportion were also different.

05/2018 Raga Gauri - Beauty from Guru Granth Sahib (Aroh, Avaroh, Pakad and Shabad) 05/2018 Raga Malkauns (Malkosh) or Hindolam - Learn to sing with notes Aroh, Avaroh, Rasa 05/2018 Raga Pahadi - Learning Notes, Aroh, Avaroh and Bollywood Songs 03/2018 Raga Pilu: Most Soothing Raga of Hindustani Classical Music 03/2018 Raga Shivaranjani Notes - Learn with Aroh, Avaroh notes with Pdf Download 02/2018 Raga Bilawal Notes: Saragam, Jaati, Lakshan Geet with Pdf Download 02/2018 Raga Bhimpalasi with Notes, Lakshan Geet (PDF Download) 02/2018 Raga Durga in Hindi with Notes, Lakshan Geet and Bandhish - Download PDF 01/2018 Which wind instruments are used in Indian Classical Music: History, Origin and Facts 12/2017 Percussion Instruments of Indian Classical Music: History, Origin and Facts 12/2017 Which String Instruments are used in Indian Classical Music: History, Origin and Facts about them 12/2017 Jaatis of Ragas - Difference between Thaats and Jaati of Raga 12/2017 Raga Asavari /Asaavari with Notes and Saragam 10/2017 Raga Yaman with Saragam, Notes, Bandhish and Lakshan Geet with Pdf Download 06/2017 What are Sruti or Shruti in Hindustani Classical Music: History Origin and Facts 06/2017 10 Thaats in Hindustani Classical Music: Most Important 05/2017 Guide to Hindustani Classical Music: You would never need anything else 05/2017 Why You Should Learn an Instrument as a Vocalist? 05/2017 Raga Kalavati and how to sing it with Aroh, Avaroh, Pakad, Lakshan Geet and Bandhish 05/2017 Raga Hamir or Raaga Hameer and how to sing it with Pakad, Lakshan Geet and Bandhish with Pdf Download 05/2017 11 Best Ragas Used In Bollywood Music 03/2017 Raaga Kedar or Raga Kedara: Learn its History, Origin and Facts with Download Pdf 02/2017 How to sing Ragas and how to improve Singing. The best 5 ways to improve your singing 02/2017 Raga Desh, Desh: With Lakshan Geet, Notes and Bandhish with Download Pdf 02/2017 Raga Bhairav or Bhairava with Lakshan Geet and Bandhish with Pdf Download 02/2017 Ashta Prahar in Indian Classical Music (Times of days) and Ragas for them 02/2017 What is Saragam or Sa Re Ga Ma? Where does Saragam or sa re ga ma come from? 01/2017 Nava Rasa (Rasas) Meaning and Usage in Indian Classical Music 01/2017 Alankar Saralies 2 (ADVANCED) 01/2017 Raga Saranga with Lakshan Geet, Notes and Bandhish 02/2011 Raga Durga with Notes, Lakshan Geet and Bandhish 01/2011 Raga Bhoop, Bhupali or Bhoopali with Notes, Lakshan Geet and Bandhish 01/2011 Alankar Saralies for beginners
05/2018 Raga Gauri - Beauty from Guru Granth Sahib (Aroh, Avaroh, Pakad and Shabad) 05/2018 Raga Malkauns (Malkosh) or Hindolam - Learn to sing with notes Aroh, Avaroh, Rasa 05/2018 Raga Pahadi - Learning Notes, Aroh, Avaroh and Bollywood Songs 03/2018 Raga Pilu: Most Soothing Raga of Hindustani Classical Music 03/2018 Raga Shivaranjani Notes - Learn with Aroh, Avaroh notes with Pdf Download 02/2018 Raga Bilawal Notes: Saragam, Jaati, Lakshan Geet with Pdf Download 02/2018 Raga Bhimpalasi with Notes, Lakshan Geet (PDF Download) 02/2018 Raga Durga in Hindi with Notes, Lakshan Geet and Bandhish - Download PDF 01/2018 Which wind instruments are used in Indian Classical Music: History, Origin and Facts 12/2017 Percussion Instruments of Indian Classical Music: History, Origin and Facts 12/2017 Which String Instruments are used in Indian Classical Music: History, Origin and Facts about them 12/2017 Jaatis of Ragas - Difference between Thaats and Jaati of Raga 12/2017 Raga Asavari /Asaavari with Notes and Saragam 10/2017 Raga Yaman with Saragam, Notes, Bandhish and Lakshan Geet with Pdf Download 06/2017 What are Sruti or Shruti in Hindustani Classical Music: History Origin and Facts 06/2017 10 Thaats in Hindustani Classical Music: Most Important 05/2017 Guide to Hindustani Classical Music: You would never need anything else 05/2017 Why You Should Learn an Instrument as a Vocalist? 05/2017 Raga Kalavati and how to sing it with Aroh, Avaroh, Pakad, Lakshan Geet and Bandhish 05/2017 Raga Hamir or Raaga Hameer and how to sing it with Pakad, Lakshan Geet and Bandhish with Pdf Download 05/2017 11 Best Ragas Used In Bollywood Music 03/2017 Raaga Kedar or Raga Kedara: Learn its History, Origin and Facts with Download Pdf 02/2017 How to sing Ragas and how to improve Singing. The best 5 ways to improve your singing 02/2017 Raga Desh, Desh: With Lakshan Geet, Notes and Bandhish with Download Pdf 02/2017 Raga Bhairav or Bhairava with Lakshan Geet and Bandhish with Pdf Download 02/2017 Ashta Prahar in Indian Classical Music (Times of days) and Ragas for them 02/2017 What is Saragam or Sa Re Ga Ma? Where does Saragam or sa re ga ma come from? 01/2017 Nava Rasa (Rasas) Meaning and Usage in Indian Classical Music 01/2017 Alankar Saralies 2 (ADVANCED) 01/2017 Raga Saranga with Lakshan Geet, Notes and Bandhish 02/2011 Raga Durga with Notes, Lakshan Geet and Bandhish 01/2011 Raga Bhoop, Bhupali or Bhoopali with Notes, Lakshan Geet and Bandhish 01/2011 Alankar Saralies for beginners