Guzheng needs to manually change key. The fundamental key is D major. However, by moving the string supporter (Mazi), Guzheng is able to play music in G, A, C major, etc. And it even can play music in non-standard key, because you can control the order and key for each string by yourself. Try this one ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-VXaTmbSdOL8.html.
