Patent ID: 7953240
Filing Date: 2011-05-31
Classification: H04R

Abstract:
1. A loudspeaker apparatus comprising: a housing having an opening formed therein; an adsorptive material disposed inside the housing, and for physically adsorbing gas inside the housing; a vibration section including a diaphragm and a diaphragm support member for supporting the diaphragm, the vibration section being disposed in the opening formed in the housing, the diaphragm support member having a stiffness; a drive section for driving the diaphragm to generate sound from the diaphragm; and a negative stiffness generating mechanism disposed inside the housing, the negative stiffness mechanism for generating a negative stiffness and for reducing an acoustic stiffness inside the housing, the acoustic stiffness acting on the diaphragm, wherein a stiffness acting on the diaphragm is determined based on the acoustic stiffness, the stiffness of the diaphragm support member, an amount by which the acoustic stiffness is reduced due to the adsorptive material, and the negative stiffness generated by the negative stiffness generating mechanism, and wherein the negative stiffness generated by the negative stiffness generating mechanism is less than a value resulting from subtracting, from the sum of the acoustic stiffness and the stiffness of the diaphragm support member, the amount by which the acoustic stiffness is reduced due to the adsorptive material, wherein the drive section includes: