定弦比二胡高四或五度：a1、e2或 g1、d2，常用音域 a1—e4或g—d4，独奏时可再扩展五度。扁八方筒高胡系由中央音乐学院王国潼和北京民族乐器厂满瑞兴研制，它的琴筒前口小，后口大，中部呈细腰形。琴筒内加装长10.2、直径4.2厘米的小竹筒，使高把位的发音格外明亮。
The gaohu ( also called yuehu ) is a Chinese bowed string instrument developed from the erhu in the 1920s by the musician and composer Lü Wencheng (1898–1981) and used inCantonese music and Cantonese opera. It belongs to the huqin family of instruments, together with the zhonghu, erhu,banhu, jinghu, and sihu; its name means "high-pitched huqin". It is the leading instrument of Cantonese music and opera ensembles. Well known pieces for the gaohu include Bu Bu Gao (,Higher Step By Step) and Ping Hu Qiu Yue (Autumn Moon On Calm Lake).
The gaohu is similar in construction to the erhu but has a slightly smaller soundbox, commonly circular, and is tuned afourth higher, to G4 and D5. Whereas most huqin are placed on top of the left thigh, the traditional gaohu is played with the soundbox held in between the knees. It has a brighter and lighter tone as compared to the erhu. It has two strings and its soundbox is covered on the front (playing) end with snakeskin (from a python). Since the soundbox is so small, the overall sound of the "gaohu" is quiet
Although originally a regional instrument used only in Cantonese music, the gaohu (in different forms and played placed on the leg, as the erhu) is used in the modern large Chinese orchestra, as part of the string family, along with the erhu, zhonghu, banhu, cello, and double bass.