[Photo provided to China Daily]

"Metal is not mainstream culture and was considered 'unhealthy', because of some perceptions associated with it－long-haired players, anger-filled lyrics and noisy sounds," Kou says. "But with more and more people being exposed to it, metal is now growing in China."

In 1997, he co-founded Suffocated with his brother, Liu Zheng, who is also the band's lead vocalist and bassist. The current lineup that includes guitarist Wu Peng and drummer Wu Gang was formed in 2005.

"At the beginning it was hard to make money from live performances but we didn't give up," he says, adding that even if they sold just six tickets for a show, they enjoyed playing for the few people gathered to listen to them.

"The most important part is to entertain yourself, whether playing onstage or while writing songs alone."

Kou and other band members always knew they could make a living with their music. But the real turnaround for them came only in 2010, when outdoor music festivals started to boom in China.

In 2012, the band also performed at the Wacken Open Air, one of the biggest heavy metal events in the world held annually in northern Germany. It was the first time for a Chinese metal band to perform at the festival. The same year, Suffocated also played on major TV channels, including CCTV, which raised their profile further.