《宋书·志·卷十九》
空侯，起初称为坎侯，漠武帝减南越酬神，祭太一神和土神时，命乐工侯晖仿照琴制作坎侯，坎的意思是说它那种坎坎的声音应合节奏。
其器不列四厢。空侯，初名坎侯。汉武帝赛灭南越，祠太一后土用乐，令乐人侯晖依琴作坎侯，言其坎坎应节奏也。
Konghou, originally called Kanhou. During the Western Han Dynasty, Emperor Wu worshipped Taili god and Tufen god when he annexed Nanyue, and ordered the musician Hou Hui to make Kanhou according to the guqin. Kan means that its melodious sound agrees with the rhythm.