Gong

A gong is an East and Southeast Asian musical percussion instrument. It is a bowl-shaped, circular metal disc which a person hits with a mallet or thick padded stick. 
Gongs produce two distinct types of sound. A gong with a flat surface gives a "crash" rather than a tuned note. In Indonesian gamelan ensembles, some gongs are made to give a beat note in the range from about 1 to 5 Hz. The use of the term "gong" for both these types of instrument is common.