1960 年 16 巻 4 号 p. 258-264
Three new reverberation chambers for sound transmission measurements were constructed beside the reverberation chambers for sound absorption measurements constructed four years ago. Airborne-sound transmission is measured through the 3. 0m×3. 0m opening on the wall between two larger chambers (each volume 164m^^3). The shape of the chamber is similar to that of the reverberation chamber for sound absorption measurement, but the size is reduced into 2/3. For impact-sound measurement, the 2. 0m×2. 0m opening on the floor is used. Under this opening the third chamber (irregular hectahedron, 68m^^3) is built. In this report, the outline of the equipments and their fundamental nature concerning the measurements are mentioned. We studied practical subjects such as the sound pressure distributions of source and receiving rooms, the size and the mounting conditions of samples, the effect of absorption power in the receiving room, and others. Then we are convinced that the equipments are useful for our future study of sound-insulating structures.