Đàn môi is the Vietnamese

Vietnamese language

Vietnamese is the national and official language of Vietnam. It is the mother tongue of 86% of Vietnam's population, and of about three million overseas Vietnamese. It is also spoken as a second language by many ethnic minorities of Vietnam...

 name of a traditional musical instrument widely used in minority ethnic groups in Vietnam

Vietnam

Vietnam – sometimes spelled Viet Nam , officially the Socialist Republic of Vietnam – is the easternmost country on the Indochina Peninsula in Southeast Asia. It is bordered by China to the north, Laos to the northwest, Cambodia to the southwest, and the South China Sea –...

. This instrument is somewhat similar to the jaw harp but there are some differences. Most Đàn môi are crafted out of a single piece of brass and attached with a string to a decorated bamboo case. Rather than being played against the teeth, like a jaw harp, the dan moi is played against the lips. This gives much more flexibility to player, leaving them freer to shape their oral cavity  as a resonance chamber

Resonance chamber

A resonance chamber uses resonance to amplify sound. The chamber has interior surfaces which reflect an acoustic wave. When a wave enters the chamber, it bounces back and forth within the chamber with low loss...

 to amplify the instrument.

Đàn môi are a traditional musical instrument of the Hmong people

Hmong people

The Hmong , are an Asian ethnic group from the mountainous regions of China, Vietnam, Laos, and Thailand. Hmong are also one of the sub-groups of the Miao ethnicity in southern China...

.

Video

• "Oh Susannah with the Vietnamese Dan Moi Jew's harp", YouTube.com.