Some bronze bells have a reed inside, so the prototype seems to have been a kind of wind instrument, but the bell seems to have gradually lost its use as a musical instrument and to have become an implement for Shinto rituals.
内部に舌（ぜつ）をもつ個体があることから、その原型は打ち鳴らす楽器であったと思われるが、次第に形式化し、祭器となったものと思われる。