In Yoshino Gypsum, our acoustic laboratory consists of three structures, "the sound source room", "the sound receiving room", and "the test specimen mounting frame". To evaluate the sound insulation performance of stand-alone walls precisely, each structure should be completely isolated from the base and, in addition to this, we have made it possible that three structures are completely isolated from each other acoustically - the first in the world.

With this system, it is possible to completely prevent the structure-borne propagation (flanking propagation) of the low frequency vibration sound from the structure of the sound source chamber to the structure of the sound receiving chamber, making it possible to accurately measure the sound insulation performance of the test specimen itself up to the TLD 80 level.