Answer:

East Asia can be viewed as one of the big four among the generally urban, literate cultural areas of the world. The other three are South Asia, the Middle East, and Europe. Around each of these major regional cultures one can find many satellite musical systems known as national forms. In most cases, the fundamental musical concepts of such national forms reflect the basic ideals of the cultural core. For example, the musics of Iran and Egypt are of one family, as are those of France and Sweden or of China and Japan. A possible fifth addition to the “big four” concept is the Southeast Asian musical culture characterized by the use of knobbed gongs. Its documents on music theory from the 18th to the 20th century combine South and East Asian concepts with indigenous insights. Its most distinctive aspects are its instrument types and resulting ensembles and forms