Western music usually thinks in terms of 12 fixed notes in an octave: C, C♯, D, D♯, and so on. Indian classical music recognizes those notes, but hears more in between. These in-between shades are called Shruti – microtonal steps or subtle pitch positions that give raags their emotional depth.
Ancient texts talk about 22 shrutis within an octave. That does not mean we literally sing 22 distinct “notes” all the time. It means: the exact placement of each swar (Re, Ga, Ma, etc.) is flexible and can shift slightly depending on the raag, the context, and the expressive intention.
How shruti differs from Western tuning
In Western equal temperament, the semitone steps on a piano are mathematically equal. The distance from C to C♯ is exactly the same as from C♯ to D, etc. This makes it easy to change keys but slightly compromises the purity of some intervals.
In Hindustani music, singers and instrumentalists often use just-intoned intervals: Re a little lower or higher, Ga slightly adjusted, Ni leaning toward Sa, and so on. These subtle shifts are shrutis. They:
- Make certain intervals ring more sweetly with the drone.
- Help distinguish closely related raags.
- Change the emotional color – for example, a slightly low komal Ga can sound more plaintive than a neutral one.
If you play along with a piano, you may notice that a good singer’s Re or Ni sometimes does not match your D or B exactly. That “out of tuneness” is actually an intentional micro-adjustment that sounds more natural against the tanpura.
Shruti in practice
Some raags prefer certain shruti placements. For example:
- In serious morning raags like Bhairav, the komal Re and Dha are often sung very low, giving a grave, meditative feel.
- In romantic raags like Yaman, Ni may be placed a bit differently in ascent vs descent to keep the flavor gentle and sweet.
Instrumentalists on fretless or flexible-pitch instruments (sitar, sarod, violin, sarangi, bansuri) can shape shrutis very finely. Vocalists use careful ear training and constant reference to the tanpura to place each note exactly where it belongs in that raag.
You don’t have to “count” shrutis as a listener. Just notice how two singers might place the same written note slightly differently in different raags – that is shruti at work, whispering secrets between the piano keys.