The northeast region of Thailand is called Isan and is made up of a majority of Lao speaking people. The music and instruments are distinct from the rest of Thailand, the main instrument being the free-reed mouth organ called khaen (pronounced “can”, it’s often spelled khene, khen, or any number of variations.) It consists of a series of bamboo pipes in two rows fitted into a wooden holder. The player breathes in and out of the wooden wind chest, fingering holes on either side. Each pipe has it’s own free reed, similar to a harmonica.
The khaen is also the dominant instrument in Lao music. This is a Lao khaen player from 1902.
Source: hajimaji.com