In Linxi Township, Sanjiang Dong Autonomous County, Guangxi Zhuang Autonomous Region, there is a kind of polyphonic mango tube called Duotong. It is to open up all the bamboo joints of the moso bamboo resonance tube, and the ends of the head and the tail are opened into a 45° oblique opening. When playing, the resonance tube is placed horizontally, and two people play the reed pipe...

The specifications of the mango tube are based on the resonance tube, and the sizes are different. The small ones are 30 cm to 70 cm high, the larger ones are 100 cm to 150 cm high, the outer diameter is 10 to 20 cm, and the inner diameter is 8 cm to 18 cm. Up to about 200 cm. According to the size and height of the resonator, the pitch of the mango can be divided into treble, alto, tenor, bass...