As in other parts of South-East Asia, particularly Burma, Thailand and Cambodia, the gong plays an important part in Vietnamese ceremonies, rites and religions.
Gongs are believed to be inhabited by spirits and represent a form of communication between humans and the spirit world. A person who possesses many gongs is highly respected, not because of wealth but because they are protected by many spirits.
All Vietnamese families own or have access to gongs and they are often used during significant feasts, festivals, the birth of a child, the death of a family member, weddings, and even repairs to the house! Often, several people in the village will gather together with a variety of gongs, as an ensemble, with gongs ranging from 10" (25cm) to 31" (80cm) in diameter.
The Vietnamese gong shares a general shape with other gongs in this region. The boss is set in a flat face, which is heavily hammer-marked. Between the flat face and the rim, there is a shallow 'channel'. The rim turns over and is either perpendicular to the face or gently slopes back in on itself. The rim is not very deep, usually between 1cm to 5cm depending on the size of the gong.
The gongs are normally made from bronze though iron and brass versions are common. The hammer marks are normally round and small and don't cut into the instrument like other Far Eastern gongs. The surface finish is a brown oxide layer which readily helps distinguish them from the neighbouring Burmese/Thai gongs which are dark green or black in colour.
Their tone is bright and bell-like for the smaller gongs, moving to a richer 'duum' tone for the larger gongs. There is a reasonable sustain, but not prolonged. Again, the best tone is obtained when played piano to mezzo forte. Anything louder tends to jar, with a sharp 'donk' sound and the sustain immediately returns to that associated with more gentle playing.