Guo Daqiang checks a new Chinese vertical bamboo flute that has just been tone-tuned in his workshop. [Photo by Su Junjie/Guangzhou Daily]

The Southern Guangdong Chinese vertical bamboo flute has become a provincial-level intangible cultural heritage as a result of development and promotion of three generations of the Guo family.

Due to high levels of materials, craftsmanship, tone and creativity, the Guo Chinese vertical bamboo flute is renowned as the "King of Chinese Vertical Bamboo Flutes" throughout the country.

Early in 1947, Lai Quan opened a flute production workshop in Guangzhou with over 10 partners. He then joined hands with other masters and established the Lingnan Flute Cooperative. Renamed as Guangzhou Lingnan Flute Musical Instrument Factory, the cooperative received great support from local government and its products were sold in many countries as representative of national musical instruments.

Guo Ruzhuo started to work in the factory in the 1960s as the main technical backbone of the research laboratory and later became Lai's son-in-law. He developed woody flutes and improved chromatic key Chinese flutes in 1963 when he was only 25 years old. Three years later, he broke a record by making a 1.8-meter-long heavyweight bass flute with experts such as musician Chen Fangde.

Guo imparted his flute-making techniques to his sons Guo Daqiang and Guo Damin as well as his daughter Guo Shanshan at the end of the 1980s. Guo Daqiang, the representative inheritor of Guangzhou Chinese vertical bamboo flute production, is now responsible for tone tuning which is the key part in making the instrument. He concludes from 30 years of flute making experience that the best bamboo for a flute should be three to four years old with a thickness of 3.5 to 4 centimeters. He thinks that the main difference between southern and northern flutes is the tone: the northern flute is more refined and traditional while the southern type is more powerful with larger volume.     

Although Guo Daqiang has taught many to make the instrument, he hasn't accepted any apprentices. He said any accepted in the future should be carefully examined for their enthusiasm for the craftsmanship and devotion necessary to promote the southern Guangdong Chinese vertical bamboo flute culture.