Tibetan Singing Bowls

Tibetan Singing Bowls like the ones used during the prayer services at the Van Hanh Buddhist Center have a long history in the practice of Buddhism. According to this website, the metal bowls date back to the time of Buddha Shakyamuni (560-480 BCE). The sounds produced are used to invoke a state of relaxation and aid in meditation. Below is a video of  typical singing bowl sounds: