An audio loudspeaker system for reproducing frequencies between 16 Hz and 700 Hz, comprising a loudspeaker housing defining an inner resonance chamber and at least two loudspeaker drivers arranged in the housing and having front faces arranged facing each other in an opposed manner. The housing comprises vertical wall elements arranged with a distance approximately defining a width of the resonance chamber, where each wall element comprises first and second side surfaces and a circumferential edge surface. A first side surface of the wall elements constitutes and inner surface of the housing and partly defines an enclosure of the resonance chamber, and a second side surface of the wall elements constitutes exterior side surfaces of the audio loudspeaker system. The loudspeaker drivers are arranged within substantially hemispherical cups arranged on the second side surfaces of the wall elements and enclosing the loudspeaker drivers in a close manner.

A wearable audio device including first and second transducer modules is provided. The first transducer module may include a first transducer. The first transducer module may further include a first enclosure having a top side defining a first slit and a bottom side defining a second slit. The first enclosure may be configured to guide a first sound pressure through the first slit, and a second sound pressure through the second slit. The second transducer module may include a second transducer. The second transducer module may include a second enclosure having a top side defining a third slit and a bottom side defining a fourth slit. The second enclosure may be configured to guide a third sound pressure through the third slit, and a fourth sound pressure through the fourth slit. The third and fourths slit may be arranged diagonally opposite the first and second slits, respectively.

An air pulse generating element is disclosed. The air pulse generating element includes a membrane, actuated according to a driving signal; a plate, wherein a chamber is formed between the plate and the membrane; wherein during a first phase of the driving signal, the membrane is actuated to change a volume within the chamber to generate an air pulse; wherein during a second phase of the driving signal, the membrane is actuated such that a gap is temporarily formed; wherein the temporarily formed gap is configured to provide a temporary air shunt to accelerate an air balancing process between a first air pressure at a first side of the membrane and a second air pressure at a second side of the membrane.

A sound system includes a seat including a seatback having a first dipole subwoofer, a second dipole subwoofer, a first speaker, and a second speaker; and a seat bottom having a third speaker. The first dipole subwoofer, the second dipole subwoofer, the first speaker, the second speaker, and/or the third speaker may be configured to receive audio signals from a receiver and provide sound corresponding to the audio signals toward an occupant position of the seat. The third speaker may be directed toward the seat back. The first dipole subwoofer, the second dipole subwoofer, the first speaker, the second speaker, and/or the third speaker may be configured to provide a sound zone for said occupant that facilitates (i) hearing of the sound by said occupant, and/or (ii) limiting transmission of the sound beyond the seat.

A sound producing device is disclosed. The sound producing device includes a first air pulse generating element, driven by a first driving signal comprising a first electrical pulse, the first electrical pulse comprises a first transition edge with a first transition polarity; and a second air pulse generating element, disposed adjacent to the first air pulse generating element, driven by a second driving signal comprising a second electrical pulse, the second electrical pulse comprises a second transition edge with a second transition polarity; wherein the first transition polarity is opposite to the second transition polarity; wherein the first transition edge generally coincides with the second transition edge; wherein air pulses generated by the first or the second air pulse generating element produce non-zero offset in terms of sound pressure level.

A low cost/high efficiency passive radiator module component includes: a tubular ported cavity structure adapted for placement inside an acoustic enclosure with a port communicating out of the acoustic enclosure and one or more pairs of passive radiators symmetrically oriented and supported on opposing side walls of the ported cavity each having a predetermined or tuned mass distribution, stiff acoustic radiating diaphragm surfaces, and spaced apart inner and outer suspensions configured to suppress diaphragm wobble that induces each pair to symmetrically vibrate inertially responsive to variable sound pressure pulses originating from an active acoustic radiator within the acoustic enclosure. Different variable acoustic pressure pulses may be detected inside and outside the ported cavity; the constricting horn connecting to the ported cavity from outside may be tuned by horn loading to achieve a desired effect.

The present invention relates to a loudspeaker including an enclosure having front portion, side portions and back portion defining an inner volume, the front portion is formed as a waveguide surface and includes at least one driver in the center of the waveguide surface and is capable to radiate the main acoustic power of the loudspeaker to ambient volume in direction of first acoustic axis, and an additional driver attached to the enclosure. In accordance with the invention the additional driver is attached inside the enclosure such that a sub volume is formed inside the inner volume, the sub volume limited by the driver, spacers between the driver and the front portion, and the front portion of the enclosure, and at least one port is adapted to open from the sub volume to ambient volume either to side portion or back portion of the enclosure and at least one resonator acoustically connected to the sub volume, the resonator being tuned to at least one of unwanted resonances of the sub volume.

An audio speaker includes an enclosure having a coupling chamber and a loading chamber, at least m radiating drivers, and at least one and no more than m−1 loading driver(s) in communication with the coupling chamber, wherein m is at least two and each radiating driver operates in common acoustic phase. The coupling chamber acts to couple the at least m radiating drivers and the at least m−1 loading driver(s), for example, and the loading chamber acts to load the loading driver(s). The at least one and no more than m−1 loading driver(s) may have a higher sensitivity than the at least m radiating drivers and the at least m radiating drivers may be arranged within the enclosure to minimize a volume of the coupling chamber. In other embodiments, the at least one and no more than m−1 loading driver(s) may be other types of inducers (e.g., an undriven loading driver(s), a drone cone, a port, or combinations thereof).

A speaker system is disclosed with user-selectable output modes including controlled directivity output modes (e.g. selectable monopole, dipole, or cardioid radiation patterns), that may be implemented with adjustable electronic delay of out-of-phase driver elements, and that provides for both even-orderharmonic distortion reduction and driver force cancellation in a compact assembly suitable for home or studio use.

An acoustic source positionable on a platform in an operating environment includes a pendulum arm and a transducer positioned on the pendulum arm. The combined arm and transducer have a natural frequency of oscillation dictated by gravity and a pendulum length. A signal generator is electrically joined to the transducer. The signal generator has a preferred frequency of operation at the natural frequency of the pendulum.