Didgeridoo (or yidaki) is none of the most ancient musical instruments form Australia. Didgeridoo is a processed bamboo or gum tree stick with 1-3 m length decorated with different paintings. The unique thing is that it sounds monotonously and has a wide ranged timbre which can be compared only with jew's harp, organ and human's voice. the technique of continuous breathing is used for playing didgeridoo. The play is accompanied by rituals and trance state.