Abstract: A system and method for externalizing sound. The system includes a headphone assembly and a localizer configured to collect information related to a location of the user and of an acoustically reflective surface in the environment. A controller is configured to determine a location of at least one virtual sound source, and generate head related transfer functions that simulate characteristics of sound from the virtual sound source directly to the user and to the user via a reflection by the reflective surface. A signal processing assembly is configured to create one or more output signals by filtering the sound signal respectively with the HRTFs. Each speaker of the headphone assembly is configured to produce sound in accordance with the output signal.

Abstract: A system and method for externalizing sound. The system includes a headphone assembly and a localizer configured to collect information related to a location of the user and of an acoustically reflective surface in the environment. A controller is configured to determine a location of at least one virtual sound source, and generate head related transfer functions that simulate characteristics of sound from the virtual sound source directly to the user and to the user via a reflection by the reflective surface. A signal processing assembly is configured to create one or more output signals by filtering the sound signal respectively with the HRTFs. Each speaker of the headphone assembly is configured to produce sound in accordance with the output signal.

Abstract: An audio enhancement method includes receiving a first plurality of input signals representative of audio captured using an array of two or more sensors, the first plurality of input signals characterized by a first signal-to-noise ratio (SNR), with the audio being the signal-of-interest. The method also includes receiving a second input signal representative of the audio, the second input signal characterized by a second SNR. The second SNR is higher than the first SNR. The method further includes combining the first plurality of input signals and the second input signal to generate one or more driver signals, and driving one or more acoustic transducers using the one or more driver signals to generate an acoustic signal representative of the audio. The driver signals include spatial information derived from the first plurality of input signals, and are characterized by a third SNR that is higher than the first SNR.

Abstract: An audio enhancement method includes receiving a first input signal representative of audio captured using an array of two or more sensors, the first input signal characterized by a first signal-to-noise ratio (SNR), with the audio being the signal-of-interest. The method also includes receiving a second input signal representative of the audio, the second input signal characterized by a second SNR. The second SNR is higher than the first SNR. The method further includes computing a spectral mask based on a frequency domain representation of the second input signal, and processing a frequency domain representation of the first input signal based on the spectral mask to generate one or more driver signals. The method further includes driving one or more acoustic transducers using the generated driver signals.

Abstract: An audio enhancement method includes receiving a first input signal representative of audio captured using an array of two or more sensors, the first input signal characterized by a first signal-to-noise ratio (SNR), with the audio being the signal-of-interest. The method also includes receiving a second input signal representative of the audio, the second input signal characterized by a second SNR. The second SNR is higher than the first SNR. The method further includes computing a spectral mask based on a frequency domain representation of the second input signal, and processing a frequency domain representation of the first input signal based on the spectral mask to generate one or more driver signals. The method further includes driving one or more acoustic transducers using the generated driver signals.

Abstract: An audio enhancement method includes receiving a first plurality of input signals representative of audio captured using an array of two or more sensors, the first plurality of input signals characterized by a first signal-to-noise ratio (SNR), with the audio being the signal-of-interest. The method also includes receiving a second input signal representative of the audio, the second input signal characterized by a second SNR. The second SNR is higher than the first SNR. The method further includes combining the first plurality of input signals and the second input signal to generate one or more driver signals, and driving one or more acoustic transducers using the one or more driver signals to generate an acoustic signal representative of the audio. The driver signals include spatial information derived from the first plurality of input signals, and are characterized by a third SNR that is higher than the first SNR.

Abstract: A system and method for externalizing sound. The system includes a headphone assembly and a localizer configured to collect information related to a location of the user and of an acoustically reflective surface in the environment. A controller is configured to determine a location of at least one virtual sound source, and generate head related transfer functions that simulate characteristics of sound from the virtual sound source directly to the user and to the user via a reflection by the reflective surface. A signal processing assembly is configured to create one or more output signals by filtering the sound signal respectively with the HRTFs. Each speaker of the headphone assembly is configured to produce sound in accordance with the output signal.

Abstract: An acoustic device that is adapted to be worn on the body of a user. The acoustic device has an array of acoustic transducers comprising at least three acoustic radiating surfaces, and a controller that is adapted to provide array control signals that independently control the relative phases and amplitudes of each of the transducers.

Abstract: An acoustic device that is adapted to be worn on the body of a user. The acoustic device has an array of acoustic transducers comprising at least three acoustic radiating surfaces, and a controller that is adapted to provide array control signals that independently control the relative phases and amplitudes of each of the transducers.

Abstract: An acoustic device includes a diaphragm, a frame, and a suspension element that couples the diaphragm to the frame such that the diaphragm is movable in a reciprocating manner relative to the frame. The suspension element includes a first surround element and a second surround element that have respective inner landings between which a region proximal to an outer edge of the diaphragm is disposed. The inner landings are mechanically coupled by an adhesive material disposed along an inner periphery of the suspension element. The adhesive material has a viscoelastic response that increases stiffness as frequency increases, resulting in a shift of a first breakup mode of the acoustic device from a first frequency to a second, higher frequency.

Abstract: An electro-acoustic driver including an acoustic waveguide includes an enclosure, an acoustic transmission line formed within the enclosure, and a plurality of acoustic transducers contained within the enclosure and disposed along a length of the acoustic transmission line. Each acoustic transducer is configured to emit acoustic energy directly into the acoustic transmission line at two separated locations along the length of the acoustic transmission line.

Abstract: An acoustic device includes a diaphragm, a frame, and a suspension element that couples the diaphragm to the frame such that the diaphragm is movable in a reciprocating manner relative to the frame. The suspension element includes a first surround element and a second surround element that have respective inner landings between which a region proximal to an outer edge of the diaphragm is disposed. The inner landings are mechanically coupled by an adhesive material disposed along an inner periphery of the suspension element. The adhesive material has a viscoelastic response that increases stiffness as frequency increases, resulting in a shift of a first breakup mode of the acoustic device from a first frequency to a second, higher frequency.

Abstract: An electro-acoustic driver including an acoustic waveguide includes an enclosure, an acoustic transmission line formed within the enclosure, and a plurality of acoustic transducers contained within the enclosure and disposed along a length of the acoustic transmission line. Each acoustic transducer is configured to emit acoustic energy directly into the acoustic transmission line at two separated locations along the length of the acoustic transmission line.

Abstract: A process for treating clarified sugar cane juice includes subjecting, in a first treatment stage, the juice to purification to remove particles larger than about 0.1 micron. The clarified sugar juice then passes through a primary ion exchange stage in which it is sequentially brought into contact with at least one strong acid cation ion exchange resin in the hydrogen form and thereafter with at least one weak base anion ion exchange resin in the hydroxide form, to effect primary demineralization of the sugar juice. Thereafter the sugar juice is passed through a secondary ion exchange stage in which it is sequentially brought into contact with at least one strong base anion ion exchange resin in the hydroxide form and thereafter with at least one acid cation ion exchange resin, to effect secondary demineralization of the sugar juice. Sugar products are recovered from the resultant purified sugar solution.

Abstract: A device for purifying liquid in a reservoir and including a vacuum chamber (1) having an inflow opening (2) and an outflow opening (3) adapted to communicate with the liquid in the reservoir through a feed conduit (4) and a return conduit (5), respectively. The return conduit (5) is provided with a pump (6) and the vacuum chamber is connected with a vacuum pump (7). The device further includes a filter cartridge (8) provided with a plurality of filter elements, each having a flow side communicating with a central passage (36) and a flow side opening into the periphery of the filter cartridge (8). The filter cartridge (8) is arranged inside the vacuum chamber, the central passage (26) of the filter cartridge communicating with the inflow opening (2) of the vacuum chamber.

Abstract: In a filtering device comprising one or more filtering elements (1) having in principle co-axially disposed through-going apertures (4) for the passage of fluid, the individual filtering element (1) consists of two identical filtering discs (2, 3) which abut each other closely along their outer peripheral edges, and which at the sides facing away from each other are formed in such a way that several filtering elements (1) abut each other closely along the inner edges adjacent to the aperture (4).

Abstract: A method and apparatus for producing intense, coherent, monochromatic light from a low temperature plasma are disclosed. The apparatus includes a housing for confining a gas at subatmospheric pressure and including a set of reflectors defining an optical cavity. At least one anode and cathode are positioned within the gas. First control means control the voltage applied to the anode and second control means independently control the temperature of the cathode. The pressure of the gas is controlled by a third control means. An intense monochromatic output is achieved by confining the gas in the housing at a controlled pre-determined reduced pressure, independently controlling the temperature of the electron emitting cathode and applying a predetermined controlled low voltage to the anode. An intermediate mode current is drawn from the cathode and produces in the confined gas, a region having a high density of metastable atomic states leading to a population inversion.