《文心雕龙·乐府》
但杜夔所调整的音律，节奏舒缓而雅正；而晋初荀勖所改制的乐器，音节却比较感伤而急促。所以阮咸曾批评他定的不协调，后来有人考查了古代的铜尺，才知道荀勖改的不对。
然杜夔调律，音奏舒雅，荀勖改悬，声节哀急，故阮咸讥其离声，后人验其铜尺。
But the rhythm of the melody adjusted by Du Kui was soothing and graceful; while the notes of the musical instruments reformed by Xun Xu at the beginning of the Jin era were instead relatively pathetic and hurried. Thus, Ruan Xian once criticized the fact that he had set them inharmoniously, and others later analyzed ancient copper rulers, and only then did they realize that Xun Xu had not carried out his reforms correctly.