Another highlight of the Sunday concert was the Double Concerto for Violin, Viola and Orchestra, featuring Julian Rachlin on violin and Sarah McElravy on viola.

In 2012, it was premiered at the Vienna Musikverein with the Bavarian Radio Symphony Orchestra conducted by Mariss Jansons, featuring Rachlin on viola.

"I was very lucky to be a close friend of Penderecki's, who was a wonderful, kind, warm and strong man. He knew exactly what he wanted for his music," said Rachlin in Guangzhou before the concert, adding that he first met the composer in 2000.

"I once asked him to write a concerto for violin and viola. Not many composers write for viola. He suggested that I learn his pieces for viola first. Then I spent 12 years learning and playing all his music for viola," says Rachlin, who played in the premiere of Penderecki's Sextet for Clarinet, Horn, Violin, Viola, Cello, and Piano in 2000.

Penderecki later wrote and dedicated two pieces to Rachlin, the Double Concerto for Violin, Viola, and Orchestra and the Ciaccona for Violin and Viola.

"The composer understood the range and sounds of viola. We cannot think of a better choice than this double concerto. This piece is very meaningful to us," says McElravy, who is Rachlin's wife. The concert in Guangzhou on Sunday was her China debut performance.