Ever since George Harrison discovered the sitar, we in the West have always regarded it - and the way it was played by Harrison’s mentor Ravi Shankar - as the quintessential sound of India. So let’s be precise: half of India, because the classical music of the south is brasher and more obviously colourful than the cloistered sonic art of the north. Hindustani music has traditionally been likened to a “house with four rooms”, representing the physical, mental, emotional, and spiritual aspects of human need. Ravi Shankar’s ragas fully vindicate this over-arching claim.

There are thousands of different ragas, each is a melodic form based on one of 72 parent scales, and each has its own character, colour, and mood. The player improvises, but the strength of the framework ensures that the result has a solid coherence. Each piece begins with an “alap”, a slow and serene invocation in which the sitar player explores the musical possibilities of the chosen raga. Then comes a rhythmic “jor”, which is followed by a fast and showy “jhala”. Connoisseurs regard the first two movements as the real test of an artist. Thereafter the drums join in and for them the rules are just as strict. They must maintain a time-cycle whose basic unit can be as long as 16 bars, and there are 360 different units from which the drummer can choose. Western musicians like to pride themselves on the sophistication of their classical music, but the classical music of Rajasthan makes unique technical demands.

To savour Ravi Shankar’s music - and he’s still going strong at age 82 - listen to any of the CDs in Angel Records’ excellent Ravi Shankar Collection. To see how his sound has been used in another medium, watch film-director Satyajit Ray’s Apu trilogy. To see how Ravi Shankar’s sound can be melded with Western strings, buy one of the recordings Yehudi Menuhin made with him in the 1970s. With its incense-laden timbre, you don’t need joss sticks to reinforce the illusion, the sitar literally exerts a timeless spell.