Delhi-6

Few music directors in present-day Bollywood dare to showcase South Asian classical music in its purest forms. Fortunately, AR Rahman is one who does. His latest release comes at the end of a particularly fruitful creative period. It began in early 2008 with notable soundtracks such as Jodhaa Akbar and Jaane Tu Ya Jaane Na, and continued with the soundtrack to Slumdog Millionaire, for which he has won a Golden Globe and a Bafta, and secured three Oscar nominations. Now, with Delhi-6, he impresses again.

The film, directed by Rakesh Omprakash Mehra, tells the story of an American-born Indian who travels to Delhi with his ailing grandmother. What was meant to be a quick visit turns into a protracted journey that places him in the heart of Chandni Chowk, the rambling, mazelike market district in Old Delhi. The number 6 is derived from the last digit of its postcode, which has become its local shorthand name.

The first song of the album, Masakali (Free Spirited) sung by Mohit Chauhan, is playful, with soft percussion and keyboards. The accordion takes centre stage along with Chauhan's voice, the music and vocals expressing the song's sentiment perfectly. Rahman's Sufi influences are evident on the second track, Arziyan (Requests), performed as a qaawali, the style of religious song made famous by the Pakistani singer Nusrat Fateh Ali Khan. In turn, Aarti (Tumre Bhavan Mein) is a sombre, Hindu prayer song – the title of which translates as In Your Abode) – delivered over restrained and minimal accompaniment.

However, it is in Bhor Bhaye (The Arrival of Dawn) that the listener is introduced to the rich tradition of Hindustani classical music. Paying close attention to harmony and melody while cleverly tying the past to the present and future, Rahman samples the voice of Ustad Bade Ghulam Ali Khan, a legendary Patiala gharana singer who died in 1968, then intersperses it with contributions by the up and coming young performer Shreya Ghoshal.

Delhi-6, the title track, is a jumble of contemporary styles featuring the Tamil rapper, BlaaZe. The song can be seen as an effort to try to capture the two sides (both geographic and metaphorical) of the city in which the movie is set. The north-central side, wherein lies Chandni Chowk, is known for its crowded lanes, mosques and delicious Mughlai cuisine. The southern part of the city, better known as New Delhi is just that: a hub of embassies and gleaming government offices alongside the well-scrubbed façades of five-star hotels and wide, tree-lined streets.

On Rehna Tu (You Stay) the producer leads the vocals in a duet with Tanvi Shah. This track is typical Rahman in at least two senses. Firstly he is known for appearing on at least one track on each of his albums and, secondly, he is responsible for discovering a number of prominent Bollywood playback singers, including Shah, with whom he first worked in 2004.

Genda Phool (Marigold Flower), meanwhile, is just beautiful. Rahman mixes looped synthesised bass into a slow and simple Rajasthani folk song. It sounds basic, but it is this kind of restrained fusion that sets him apart. Indeed this has the subtle, contemporary appeal could place it squarely in the Indian charts.

In short, this soundtrack is not for those looking for cliched Bollywood music, which often involves little more than unimaginative beats designed for actors to dance to, staidly remixed by popular DJs. Delhi-6 is in a different class altogether. With its exploration of the delicate nuances of South Asian classical music, it rewards careful listening. Whatever happens at the Oscars we can expect Rahman to be more of a presence in the international scene from now on, bringing his eastern sensibilities with him and applying them to the music of the world.