An earlier form of music notation from the Tang era survives in just one manuscript , dated to the 7th century CE , called Jieshi Diao : You Lan ã ç cents # ç è å 1\/2 è ã ( Solitary Orchid , in Stone Tablet Mode ) . An earlier form of music notation from the Tang era survives in just one manuscript , dated to the seventh century CE , called Jieshi Diao Youlan ( Solitary Orchid in Stone Tablet Mode ) .