The Kaen is a wind instrument widely used in East Asia. Historical records reveal that it has been in use for several thousands of years. It has different names in different places. The Hmong people call it Keng (เค่ง/เค้ง); the Chinese call it Sa-ang (ซะอัง); the Korean call it Saeng (แซง); and the Japanese call it Soh (โซว). There are some differences in shapes and appearances according to the local preferences and usage in each locality.
         The Kaen is made of a specie of bamboo called Maai Pai Hia (ไม้ไผ่เฮี้ย) or Maai Goo Kaen (bamboo used to make Kaen pipes—ไม้กู่แคน). The bamboo is cut into graded lengths. In the middle of each pipe (Goo) a slit is cut for attaching a metal reed to produce the vibration when it is blown. The reed is generally made of brass (called the golden reed) or a mixture of copper and silver (called the silver reed). Then the pipes are put into the mouth piece made of a piece of hard wood such as the root of Burmese ebony or Maai Nam Gleay (ไม้นำเกลี้ย). The mouth piece is called Tao Kaen. It is in the position for the musician to hold and to blow when playing the instrument. A caulking material is used to seal all small openings and to keep the blown air inside the mouth piece (Tao Kaen). Each bamboo pipe is pierced with a hole at the position just above the mouth piece as finger hole.
         There is a variety of Kaen, named according to the number of pipes, starting from 3 pairs to 9 pairs. The Kaen that are widely used in the Northeastern Region are Kaen Hok, Kaen Paed and Kaen Gao. (The Kaen with 6, 8 and 9 pairs of pipes respectively)