What's 'roundness' in the 'nine properties' of GuQin timbre? How to explain or describe it? In my opinion, it could be, just like a group or a family of seven brothers, and they all get on well with each other, very harmony. On the other hand, they all share the same family feature in timbre presentations.

其实，“圆”，是古琴很难得的品性
很多南方琴（尤其扬州琴），不具备‘圆’的特点。

具体诠释一下‘圆’：
圆= 饱满，浑厚（醇厚），不单薄，不干瘪

圆= 饱满，浑厚（醇厚），不单薄，不干瘪
指声音上的饱满和浑厚感。