This is a question of ignorance because I am confused. The cymbal is part of the drum set so can it be considered a drum? And if so then the gong is also a drum because it is a big cymbal. Anyway, this issue cropped up in one of our travels in Bangkok. There was a gong in one temple that is hit to produce a loud sound to signal the start of prayers. And that started the query about the gong being a drum or not.