Hill, Van Santen, Steadman, Chiara & Simpson
Speaker system
 A speaker system employs: a baffle board in front of a cabinet made of wood, with a woofer mounted on the baffle board; and a sub-baffle board having a medium-range speaker and a tweeter mounted thereon. The sub-baffle board comprises a metal board and a damping plate such as a rubber plate laminated on the metal plate. 
Sony Corporation
H H
H04R H04R
inventional inventional
Mamoru Shigeru Shinichi
Osata Okazaki Watanabe