Yu Quan members Chen Yufan (left) and Hu Haiquan show the digital flash disc of their new album Recyclable. Zou Hong / China Daily

"Music is always the core for Yu Quan," says Hu, 38, who with Chen, writes original material. "I sing about our lives, love, brotherhood, friendship, homesickness and everything. I guess that's why we reach so many fans' hearts."

With more than 6 million copies sold, the duo broke the conventional CD format and released the new album in digital flash disc online.

Ever since their debut album, The Most Beautiful, the duo has been known for their diversified music style and upbeat spirit. They have released 12 albums so far.

Their live shows have also cemented their reputation with an improvisational style and warm atmosphere.

Since 2010, Yu Quan has held a Christmas concert each year. On Dec 24, they will continue the tradition with their Life is Like A Playground concert.

"We are proud to be a pop duo that caters to both the old and the young. Every time, our concerts become a huge karaoke bar," Chen says.

Both agree that a common passion for music and brotherhood are at the root of Yu Quan's success.

"There has been no change in our attitude toward music. We still value our friendship and partnership as much as ever and we are filled with hope," Chen says.