Hulusi is also called Calabash flute. It is mainly popular in the Dehong and Lincang areas of Yunnan where the Dai, Achang, Wa, Deang and Blang ethnic groups live together. The gourd flute is often used to play folk tunes such as folk songs, and is most suitable for playing music or dance music with smooth melody. The tunes generally have more long tones, rich choruses, and the music is soft and harmonious, which can better express the player's thoughts and feelings.
The Hulusi of the Dai people inserts three bamboo tubes of different lengths side by side into the gourd. The lower end of the bamboo tube is embedded with a copper reed, and a longer bamboo tube in the middle has seven sound holes, which can blow out an octave melody sound, called the main tube. The remaining two are auxiliary pipes, which only have reeds and no sound holes. When playing, the main pipe plays the main melody, and the auxiliary pipes emit single notes, forming a harmonious effect and a soft and pleasant timbre. The cucurbits of other ethnic groups are similar in shape to those of the Dai people.
In the late 1950s, the Yunnan Provincial Song and Dance Troupe first expanded the range of Hulusi to 14 tones. In recent years, some literary and artistic groups in Beijing have made two new gourd flutes. Among them, the six-tube calabash flute can play single notes, double notes, single melody plus sustained tone, and two harmonic melody plus sustained tone. It not only maintains the unique timbre and style of the original instrument, but also increases the volume, expands the range, and enriches the sound color and performance.