|By Haresh Bakshi
The spelling: sruti (the first letter "s" as the diacritical Roman
symbol) has been used by Sir Monier-Williams, Walter Kaufmann, Ashok Da Ranade,
L. Subramaniam; shruti, by Alain Danielou, Swami Prajnananda and several
others. It is a question of how we represent the Sanskrit sound, as
in the English word shrewd , for transliteration into the Roman alphabet.
Lack of standardisation is the hallmark of Sanskrit terms. Shruti has
been variously translated as: microtone, microtonic interval, interval, step
etc. It is mainly determined through fine auditory perception or grasp.
The number of sounds falling within a scale is infinite; but the number which
can be differntiated (or perceived, or grasped) is 22. These 22 shruti-s
are further grouped into five classes, bringing in the concept that a shruti
is not only an auditory perception, but also a distinct expression to the
listener's mind. There is a broad agreement that shruti-s are not equal;
that the seven notes are the sounds selected from among these 22 shruti-s;
that each note is established on its first shruti; that shruti-s can be reproduced
on a string instrument, in terms of various vibrating lengths; that shruti-s
can, therefore, be stated in terms of frequencies, though Indian music, being
truly modal, is built on the relationship of sounds with the tonic (also
called the reference note, key etc.).
The earliest mention appears to have been made in Bharat muni's Natyashastr
(about 500 B.C.). later references include Narada of Shiksha (1st century
A.D.), Kohala (quoted in Brihaddeshi) Dattila's Brihaddeshi, and several
later works. "samvaditaa" (consonance) is defined in terms of shruti-s
like this: The distances of 23, 13, and 9 shruti-s imply perfect consonances.
The distance of 23 shruti-s indicates the same note, but in the higher octave.
The 13-shruti distance shows the distance of the fifth, called shadja-panchama
bhaava. The 9-shruti distance means the distance of the fourth,
called shadja-madhyama bhaava.
The shruti-s may be grouped according to two scale types, or grama-s, namely
shadja grama, and madhyama grama:
Shadja grama: S 4 R 3 G 2 m
4 P 4 D 3 N 2
Madhyama grama: S 4 R 3 G 4 m 2
P 4 D 3 N 2
Shruti is a part of tonal concept. Talented singers use them, regularly
and unknowingly, as part of their musical repertoire. Quite often,
even the raga-s have their notes established on shruit-s, rather than the
usual notes. For example, the "komal Re" (Db, if Cis the tonic) of
the raga Todi, is really a microtene, lower than the usual location of "komal
Re" in the Indian scale. Even the singers of a capella, use the notes
of the harmonic scale, not the notes of the tempered scale; this is because
of absence of accompaniment on piano or any instrument with fixed, tempered
scale. So, singing correct microtones comes naturally to the voice
of a talented singer.