The influence of the tambura drone on the perception of proximity among scale types in North Indian classical music

The classical music of India is based on both theoretical and acoustical systems. The classification of North Indian rags by scale type, or That (framework), is one such system. A series of experiments was designed to determine a possible perceptual basis for the system of That groupings, and to test cross-culturally what effect the psychoacoustical context provided by the tambura drone may have on the perception of proximity among the most commonly used Thats.