It appears that the trong chiến name was adopted throughout Vietnam, however, these do not share a common proportionate blueprint. As a result, some of the drums can look visually different.
The following five drums are from different museums or references. They have the same name, but when compared they clearly show different proportions. The formula used here is: the larger side, the height (H), divided by the diameter of the membrane surface (D), to give the proportion (P).
Chiến 1...