Abstract: A high-frequency (HF) sound-emitting device is provided, which comprises an open-ended hollow housing, an acoustic oscillator arranged inside the hollow housing and configured to generate HF sound oscillations, and a sound-emitting membrane attached to the acoustic oscillator. The sound-emitting membrane comprises a paper-based composite material layer, a metal layer, and a coating layer. The paper-based composite material layer has a top surface facing the open end of the hollow housing. The metal layer is provided on the top surface of the paper-based composite material layer and configured to reproduce the HF sound oscillations. The coating layer is provided on the metal layer and has one or more slots through which the metal layer is visible. The coating layer is made of a material incapable of reproducing the HF sound oscillations. With this configuration, the sound-emitting device may emit a fractal-polarized sound field.

Abstract: Aheadphone configured to emit a fractal-polarized sound field is provided. The headphone comprises a sound-emitting membrane, an acoustic oscillator, and an ear pad. The sound-emitting membrane comprises a paper-based composite material layer, a metal layer, and a coating layer. The paper-based composite material layer has a front surface and a rear surface, with the front surface facing a user ear. The metal layer is provided on the front surface of the paper-based composite material layer and configured to reproduce HF acoustic oscillations. The coating layer is provided on the metal layer and has one or more slots through which the metal layer is visible. The coating layer is made of a material incapable of reproducing the HF acoustic oscillations. The acoustic oscillator generating the acoustic oscillations is attached to the rear surface of the paper-based composite material layer. The ear pad is configured to cover the coating layer.

Abstract: The present disclosure relates to an electrodynamic actuator configured to operate within a wide frequency range up to the entire spectrum of audio frequencies (20 Hz to 20 KHz). The actuator comprises an open-ended hollow body, a package-type magnetic system comprising one or more pairs of magnets arranged in the hollow body, a sound-emitting membrane arranged externally to the hollow body, a support frame extending from the membrane into the hollow body and having two or more coils attached thereto, and conductive tracks connecting each of the coils with an AC power source. Each pair of magnets comprises two coaxially fixed magnets, one of which surrounds another in the form of a ring. There is a magnetic gap between the magnets in each pair of magnets. Moreover, the magnets in each pair of magnets have different magnetizations, so that their magnetic fields are directed in opposite directions.