Mouth harps are played by most of the tribal groups in northern Thailand and the surrounding region. Used for storytelling and courtship because the sounds produced are so similar to those of spoken language, most are made of bamboo. Only the Hmong use brass ones like these, calling them ‘ncas’; these were handmade in Vietnam.

Photo courtesy of Victoria Vorreiter, from her book Songs of Memory, Traditional Music of the Golden Triangle. Hmong musician is Tuam Yaj  in Ban Ga Lae, Chiang Rai Province, Thailand