shruti
The smallest perceptible interval of pitch in Indian classical music, forming the microtonal basis of the system.
In Depth
Indian music theory recognises 22 shrutis within each octave, far more than the 12 semitones of Western music. These microtonal intervals give Indian music its distinctive character and allow for subtle pitch inflections impossible in equal temperament. Shrutis are not fixed mathematical divisions but rather perceptible pitch distinctions that trained musicians learn to hear and produce. The shruti box, a small bellows-driven instrument, provides a drone reference pitch.
Western music collapsed 22 shrutis into 12 equal semitones for practical reasons, sacrificing the subtle pitch shadings that give Indian music much of its emotional power.