A gong is a musical instrument that belongs to a group called struck idiophones. It’s a flat circular disk of bronze or brass with a convex, sometimes corrugated surface and slightly recurvated edges. It usually hangs or is placed on a special stand. It starts vibrating when struck with a soft head mallet. Type of the sound depends on a spot that is hit.
The disk’s vibrations transfer to the air and cause formation of increased and decreased air density areas. This results in an acoustic wave that you can hear – but also feel.
Strike the gong with the mallet somewhere above its center. Listen to the sound it makes. Place your hand near the gong’s surface, not touching it. You will feel vibrations of the air surrounding the gong. Move your hand around and explore how the intensity of vibrations changes in different places. Remember: never strike the very center of the gong. It could damage the instrument.