The application discloses a passive back
cavity wall based on a plane
sound field, comprising a
magnetic structure, a magnetic film and a pressure-sensitive
adhesive layer; each
magnetic structure is a ferrimagnetic
magnetic structure, and a plurality of magnetic structures are spliced through the pressure-sensitive
adhesive layer to form a U-shaped or H-shaped magnetic cavity structure matched with an active device; each magnetic cavity structure is arranged at a central position directly below the corresponding active device and is fixedly connected with the corresponding position of the lower surface of the plane material through the pressure-sensitive
adhesive layer; a magnetic film matched with the magnetic cavity structure is arranged on the outer surface of each magnetic cavity structure; each magnetic film has
magnetism, is preliminarily fixed through the magnetic attraction generated between the magnetic film and the corresponding magnetic cavity structure, and is used for adsorbing and sealing the corresponding magnetic cavity structure, so that the passive back
cavity wall matched with the active device is formed. The application assists in increasing the low-frequency
vibration amplitude and displacement through the induced
magnetic field formed by the passive magnetic cavity structure, and improves the
low frequency and
high frequency.