Physical properties of a reed (Phragmites australis) used for the vibrating reed of Japanese traditional oboe (Hichiriki)

摘要

Hichiriki is a Japanese traditional oboe used for Japanese ancient court music, and the vibrating plate of the hichiriki is made by a reed (Phragmites australis). We observed the anatomical structure of reed selected by experts, and measured their density and transverse compressive strength to clarify the basic requirements for quality instruments. Within an internode, the upper part was always thinner and denser than the lower part, depending on the thickness of low density parenchyma layer beneath the cortex. The selected reed was slightly thicker and denser than unselected reed, whereas those differences were not significant. On the other hand, the transverse compressive strength of selected reed was significantly greater than that of unselected reed, and the upper part showed highest strength. It is considered that sufficient transverse strength is required while thinner i.e. deformable upper part is preferred for hichiriki, because an end of reed culm is compressed to form the closed end of double-reed.