Abstract: Electroacoustic drivers that can be utilized in loudspeaker systems that utilize drivers having a magnetic negative spring (MNS). The magnets of the MNS can be arranged for radial stability and/or to provide for linear magnetic forces. A variable reluctance device can be used to vary the resonant frequency of electroacoustic driver in response to a feedback signal.

Abstract: Electroacoustic drivers that can be utilized in loudspeaker systems that utilize drivers having a magnetic negative spring (MNS). A variable volume device, such as a bellow, is used to vary the enclosed air volume of the sealed chamber of the loudspeaker.

Abstract: Force transducers for use in electrostatic drivers, including electrostatic drivers that can be utilized in loudspeaker systems that utilize drivers having a magnetic negative spring (MNS) (such as reluctance assist drivers (RAD) and permanent magnet crown (PMC) drivers). The electroacoustic drivers having the force transducers can be used at all audio frequencies, including subwoofer frequencies.

Abstract: Voice coil actuators and loudspeakers containing same. The voice coil actuators include moving voice coil assemblies that have multiple segments. Each segment of a moving voice coil assembly is separately controlled by an amplifier, one channel of an amplifier, and combinations thereof utilized in combination with a position sensor that senses the position of the moving voice coil assembly. By this arrangement, the voice coil actuators produce a linear force per unit current throughout the range of motion while obtaining the benefits and advantages associated with both over-hung and under-hung voice coil actuator designs.

Abstract: Electroacoustic drivers that can be utilized in loudspeaker systems that utilize bidirectional force electromagnet transducers or piezoelectric transducers. The electroacoustic drivers can include motion amplifiers such as lever arms. The electroacoustic drivers can be used at all audio frequencies including frequencies below 500 Hz.

Abstract: Electroacoustic drivers that can be utilized in loudspeaker systems that utilize drivers having a magnetic negative spring (MNS) (such as reluctance assist drivers (RAD) and permanent magnet crown (PMC) drivers). The electroacoustic drivers can be used at all audio frequencies, including subwoofer frequencies. The magnetic negative springs of the electroacoustic drivers can cancel, or partially cancel, the large pressure forces on a sound panel (of an audio speaker) so that substantial subwoofer notes can be efficiently and cost effectively produced in small/portable speakers. The electroacoustic drivers can include a stabilizing/centering mechanism to overcome the destabilizing forces of a MNS that are too large for a voice coil alone to produce.

Abstract: Electroacoustic drivers that can be utilized in loudspeaker systems that utilize drivers having a magnetic negative spring (MNS) (such as reluctance assist drivers (RAD) and permanent magnet crown (PMC) drivers). The electroacoustic drivers can be used at all audio frequencies, including subwoofer frequencies. The magnetic negative springs of the electroacoustic drivers can cancel, or partially cancel, the large pressure forces on a sound panel (of an audio speaker) so that substantial subwoofer notes can be efficiently and cost effectively produced in small/portable speakers. The electroacoustic drivers can include a stabilizing/centering mechanism to overcome the destabilizing forces of a MNS that are too large for a voice coil alone to produce.

Abstract: Electroacoustic drivers that can be utilized in loudspeaker systems that utilize drivers having a magnetic negative spring (MNS). The MNS has an asymmetrical magnet design so that it can cancel or partially cancel the differential air pressure force that is different between inward and outward movement of a sound panel.

Abstract: Electroacoustic drivers that can be utilized in loudspeaker systems that utilize drivers having a magnetic negative spring (MNS) (such as reluctance assist drivers (RAD) and permanent magnet crown (PMC) drivers). The electroacoustic drivers can be used at all audio frequencies, including subwoofer frequencies. The magnetic negative springs of the electroacoustic drivers can cancel, or partially cancel, the large pressure forces on a sound panel (of an audio speaker) so that substantial subwoofer notes can be efficiently and cost effectively produced in small/portable speakers. The electroacoustic drivers can include a stabilizing/centering mechanism to overcome the destabilizing forces of a MNS that are too large for a voice coil alone to produce.

Abstract: Electroacoustic drivers that can be utilized in loudspeaker systems that utilize drivers having a magnetic negative spring (MNS) (such as reluctance assist drivers (RAD) and permanent magnet crown (PMC) drivers). The electroacoustic drivers can be used at all audio frequencies, including subwoofer frequencies. The magnetic negative springs of the electroacoustic drivers can cancel, or partially cancel, the large pressure forces on a sound panel (of an audio speaker) so that substantial subwoofer notes can be efficiently and cost effectively produced in small/portable speakers. The electroacoustic drivers can include a stabilizing/centering mechanism to overcome the destabilizing forces of a MNS that are too large for a voice coil alone to produce.

Abstract: Electroacoustic drivers that can be utilized in loudspeaker systems that utilize drivers having a magnetic negative spring (MNS) (such as reluctance assist drivers (RAD) and permanent magnet crown (PMC) drivers). The electroacoustic drivers can be used at all audio frequencies, including subwoofer frequencies. The magnetic negative springs of the electroacoustic drivers can cancel, or partially cancel, the large pressure forces on a sound panel (of an audio speaker) so that substantial subwoofer notes can be efficiently and cost effectively produced in small/portable speakers. The electroacoustic drivers can include a stabilizing/centering mechanism to overcome the destabilizing forces of a MNS that are too large for a voice coil alone to produce.

Abstract: Nano-electromechanical systems (NEMS) devices that utilize thin electrically conductive membranes, which can be, for example, graphene membranes. The membrane-based NEMS devices can be used as sensors, electrical relays, adjustable angle mirror devices, variable impedance devices, and devices performing other functions. The NEMS devices have a serpentine shape arrangement of the electrically conductive membrane. The electrically conductive membrane can be controllably wicked down on the edge of the oxide cavity to increase sensitivity of the NEMS device.

Abstract: Electroacoustic drivers that can be utilized in loudspeaker systems that utilize drivers having a magnetic negative spring (MNS) (such as reluctance assist drivers (RAD) and permanent magnet crown (PMC) drivers). The electroacoustic drivers can be used at all audio frequencies, including subwoofer frequencies. The magnetic negative springs of the electroacoustic drivers can cancel, or partially cancel, the large pressure forces on a sound panel (of an audio speaker) so that substantial subwoofer notes can be efficiently and cost effectively produced in small/portable speakers. The electroacoustic drivers can include a stabilizing/centering mechanism to overcome the destabilizing forces of a MNS that are too large for a voice coil alone to produce.

Abstract: Pumping systems that have pumping system units utilizing venturi pumps. Such pumping systems can be used in speakers, to propel drones, and other applications. Actuation of the venturi pumps can be by piezoelectric actuators, magnetic actuators, electrostatic actuators, and other similar actuators.

Abstract: This disclosure relates to loudspeakers that use one or more stacks of electrically actuated cards that pump air through vents to produce sound waves in response to an acoustic signal. Each stack can include several electrostatic actuator cards that are stacked on top of each other and collectively operate to pump air through a vent to produce a sound wave. Each card may include an electrically conductive membrane that is pushed/pulled between two electrically conductive stators. As the membrane is pushed and pulled along a first axis, air is pumped through vents in a direction orthogonal to the first axis. In one embodiment, stacks of cards can be arranged in series to increase sound pressure generated by the loud speaker. In another embodiment, a single stack of cards can be driven with relatively high electric field strength to increase the sound pressure generated by the loud speaker.

Abstract: This disclosure relates to loudspeakers that use one or more stacks of electrically actuated cards that pump air through vents to produce sound waves in response to an acoustic signal. Each stack can include several electrostatic actuator cards that are stacked on top of each other and collectively operate to pump air through a vent to produce a sound wave. Each card may include an electrically conductive membrane that is pushed/pulled between two electrically conductive stators. As the membrane is pushed and pulled along a first axis, air is pumped through vents in a direction orthogonal to the first axis. In one embodiment, stacks of cards can be arranged in series to increase sound pressure generated by the loud speaker. In another embodiment, a single stack of cards can be driven with relatively high electric field strength to increase the sound pressure generated by the loud speaker.