The bronze bell is actually an alloy of copper and stannum and its cross-section is not round or an ellipse but an olive figure, and its main body consists of two arc boards resembling Chinese tile. This unique structure means the bell will strike up different keys in different parts. Bell performances of the Shang Dynasty (About 1600-1100BC) were usually performed in groups, usually with three bells to a group, and the bells were suspended over shelves.
In the later Spring and Autumn period (770-476BC), the chime bells were usually 9 bells to a group. By that time, a suit of 13 chime bells with integrated music of equal temperament had also emerged.
Except for 9 bells in a group, the chime bells of the Warring States (475-221BC) also had 13 or 14 bells to a group.
The most attractive chime bells were excavated from marquis Zeng's tomb of the Warring States period. They consisted of 64 bells and were suspended from three different layers of a rectangular shelf. The first layer consisted of 19 suspended bells while the second and third layers were 45 suspended bells in total. All the bells were exquisite and performed well, and it has been the biggest band consisting of bells and drums so far.
Drum
The drum is a traditional percussion instrument of China. Since the drum has a function of resonance, it originally served to boost the morale of the army.