An obsessive passion to revive a nearly forgotten music enjoyed by China's elite more than a thousand years ago has cost Li Kai his wife, his job and most of his savings.

Li said that 60 years ago, when the People's Republic was founded following decades of civil war and revolution, there were 50 groups practising this music in Shaanxi.

Now, after the ravages of the Cultural Revolution in the 1960s and 1970s which sought to wipe out China's ancient traditions, only 12 groups remain throughout the country, totalling 200 people.