"It’s like the rush of a marsh on a midsummer night with a million crickets, or the howling wind stirring the power lines outside a cabin in backwoods Idaho, or the hushed roar of the stream in front of a hermit’s cave above Dehradun"

(author Alexander Keefe, in Lord of the Drone: Pandit Pran Nath and the American Underground)

Ask a random person in the street to tell you something about Indian music. The answer you get could be something like: a) dunno, b) didn’t Jay-Z have some track with Indian music in it? or c) doesn't it have this droning sound in it? All would be valid in their own ways, but the last is most interesting, because it points to how the sound of the tanpura drone says ‘Indian music’ like nothing else.

In a performance of Indian classical music, the drone is usually the first and last sound to be heard. It is created by the tanpura, a long necked, fretless lute whose open strings are plucked in a continuous loop throughout both performance and practice. No traditional concert musician would play without it, just as a good chef would very rarely cook without salt. Like salt, it remains in the background, enhancing and supporting the flavours of the raga without taking centre stage.

It holds a unique place in the instrument family, being neither melodic or rhythmic. Simultaneously supportive, yet independent, the rhythm at which it is played need not correspond to the rhythm of the piece. The four or five strings are always played open, usually tuned to Pa-Sa-Sa-Sa and played in this order to provide a harmonic resonance on the basic or tonic note. Each string produces its own cascading range of harmonics as it is played, sometimes compared to a prism refracting white light into different colours.

Though Indian music utilises many drone instruments, some blown like the ottu pipe and shankha (conch shell), or pumped like the swarpeti box, none boast the rich tonal spectrum of the tanpura. This overtone-rich, sustained buzzing is known as jivari, or life-giving essence.

Tanpuras are very carefully tuned, first with large pegs, then with smaller fine tuners at the base of the instrument, and finally with the adjustment of cotton threads that shift the placement of the string over the carved bridge, also (somewhat confusingly) called the jivari. The ultimate aim is for each string to produce a rainbow in one tone. The precise pursuit of these tonal shades relative to the subtle qualities of the raga is never ending, and forms an important part of a classical musicians sadhana or dedication. By the endless practice of tuning, the musician’s ear is sharpened and refined.

The tanpura has a few different forms and styles dependent on the preference of the performer. The Miraj style is favoured by Hindustani performers and made of a dried gourd with a wooden neck. These are available in both larger male and smaller female forms to accommodate different pitches. The Tanjore style is used more commonly by South Indian musicians and is made entirely from wood. The smallest form is the tanpuri, only two or three feet long with a lighter, less dominating sound often used for accompanying solo strings or for ease of transport.

These days electronic tanpuras sometimes replace their manual counterparts due to ease and practicality. Even more recently, a crop of smartphone apps such as iTanpura have been created to allow tanpuras to literally be pocket-sized. But most musicians still feel that the digital version will never replace the dynamic quality of the real thing, and that the ease of switching on a button is encouraging a lower standard of tuning ability amongst young musicians.

According to the ancient teachings of Indian music, the tanpura expresses the resonant sound that is eternally present throughout creation, sometimes known as om, the sacred syllable. The sustained notes found in nature have long been an inspiration for musicians who would practise in the outdoors.

In the 1986 film In Between The Notes: A Portrait of Pandit Pran Nath, the legendary Kirana gharana singer recounts how during his five year stay in the Tapkeshwar caves, he had no tanpura, but would stand in the nearby creek to practise, with the running note of the current providing the supportive drone. He was a renowned ‘devotee' of these instruments and would spend long hours tuning his tones until they began to sing the deepest essence of the raga to be explored.

Modern day musicians often joke about unintentionally singing along with the drone of washing machines or electrical appliances. Next time you listen to a tanpura, get up close and see how many tones you can hear - it certainly is a wonder.

Listen to the music | Young Dhrupad singer Pelva Naik explains the importance of the tanpura to her art form. Recorded by Darbar on location in India.

Jahnavi Harrison is a multi-disciplinary artist, specialising in vocal music, Kirtan meditation, and Indian devotional dance.

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