Abstract: A microphone includes a microphone case having an opening in front of the microphone case accommodating a microphone unit in the opening; a piece of double-sided adhesive tape whose back side is attached along the opening of the front side of the microphone case; and a filter adhered to a front side of the piece of the double-sided adhesive tape so as to cover the opening of the microphone case, wherein the piece of the double-sided adhesive tape is provided with sound introduction holes which introduces sound waves to the microphone unit through the filter. This configuration enables to provide a microphone easily and in a short time having desired frequency response characteristics without raising costs.

Abstract: A sensor device includes a sensor element, a converter, and an output unit. The sensor element includes a sheet-like dielectric layer including an elastomer composition and a top electrode layer and a bottom electrode layer each including an electroconductive composition containing carbon nanotubes. The top and the bottom electrode layers are formed on a top surface and a bottom surface of the dielectric layer, respectively, and are at least partially opposed to each other across the dielectric layer. The at least partially opposed portions of the top and the bottom electrode layers constitute a detection portion, and the dielectric layer reversibly deforms to change an area of a main surface of the dielectric layer. The converter electrically is connected to the sensor element and converts capacitance at the detection portion that varies in accordance with the deformation of the dielectric layer to electric characteristics.

Abstract: The present disclosure provides an earphone device with sound adjustment capability that allows a user to dynamically adjust sound acoustics resonating from the device. In one aspect, the earphone device includes a housing having an acoustic output port. The acoustic output port is adapted to receive an audio signal. In this regard, sound resonates from the acoustic output port based on the audio signal. The earphone device also includes a telescopic portion having a hollow tube portion attached to the housing. The hollow tube portion may be in communication with the acoustic output port. The telescopic portion is configured to receive a fitting member. The fitting member is configured to adjust a bass range of the outputted sound resonating from the acoustic output port by passing through the telescopic portion so as to adjust a length of the hollow tube portion.

Abstract: A speaker assembly including a sound radiating surface suspended over a magnet assembly, a suspension member for suspending the sound radiating surface over the magnet assembly, a voice coil extending from a bottom side of the sound radiating surface, and a capacitive displacement sensor for sensing a movement of the sound radiating surface. The capacitive displacement sensor including a first conductive plate fixedly positioned over the sound radiating surface and a second conductive plate coupled to the sound radiating surface and vertically aligned with the first conductive plate, and wherein the second conductive plate is confined to an area that is entirely radially inward of the voice coil.

Abstract: There is provided a headset having at least one microphone for detecting ambient noises, at least one electroacoustic reproduction transducer and a control unit for controlling the headset. The headset also has a digital active noise reduction unit for performing digital active noise reduction based on the ambient noises recorded by the microphone. The headset further has a data interface for receiving data and/or parameters for the headset and for outputting data and/or parameters stored in the headset.

Abstract: A system includes a first scanner having an inflatable membrane configured to be inflated with a medium to conform an exterior surface of the inflatable membrane to an interior shape of a cavity. The medium attenuates, at first rate per unit length, light having a first optical wavelength, and attenuates, at a second rate per unit length, light having a second optical wavelength. An emitter is configured to generate light to illuminate the interior surface and a detector is configured to receive light from the interior surface. The scanner further includes a processor configured to generate a first electronic representation of the interior shape based on the light. A design computer is configured to modify the first electronic representation into a three-dimensional shape corresponding to at least a portion of the interior shape and a fabricator configured to fabricate, based at least on the modified first electronic representation, an earbud.

Abstract: A cart stores a plurality of mobile computing devices. The cart includes a plurality of slots defined by opposed plates. Each of the slots is configured to accept a corresponding mobile computing device. Each of the plates includes a first transmit coil for wirelessly transmitting power to a receive coil in the corresponding mobile computing device.

Abstract: In accordance with the example embodiments of the invention there is at least a method and apparatus to perform receiving, with at least one diaphragm of a device placed on a skin of a living body of a human being or animal, acoustic data of the living body; determining digitized data from the acoustic data of the living body; and sending the digitized data towards an analytics system for a medical diagnosis associated with the living body; determining a relationship between the digitized data and health conditions of the human being or animal; and applying the relationship to a diagnosis of the health conditions of the human being or animal.

Abstract: A system and method for diagnosing problems in a medical imaging system. In some implementations, problems with the medical imaging system are determined by encoding information into an image relating to system settings or other data, and using the information to diagnose possible problems with the image and/or the medical imaging system.

Abstract: A wireless stethoscope is described, having wireless sensors that are enclosed in disposable pads so that the same pads are not used on more than one patient, preventing cross-infection of patients associated with conventional stethoscopes. The present wireless stethoscope also detects pulmonary sounds and cardiac sounds, allowing the user to monitor one or the other without interference. Also described is a method for diagnosing a pulmonary condition using the wireless stethoscope.

Abstract: A mobile device-based stethoscope system that transmits, records, and analyzes sounds to generate a list of matching conditions and facilitates easy attachment across various electronic medical record platforms and other means of communication. The invention is configured to allow the use of either an integrated wireless stethoscope, or an in-line adapter for a conventional stethoscope. Patient sounds are sent from the selected stethoscope head to the mobile device having a software application that allows for the analysis, attachment, and further manipulation of the data.

Abstract: A system and method for remotely monitoring a medical device includes a sensor for monitoring sounds in the proximity of a medical device. The sensor has a microphone for producing an audio supervision signal. There is a memory and processing circuit for storing the audio supervision signal and having a monitoring program that includes device alarm characteristics, and a status flag file, and a communication circuit for communicating with a server. There is a server in communication with the sensor and a remote terminal in communication with the server. The monitoring program is configured to analyze the audio supervision signal and to refresh the status flag file to a value based whether the audio supervision signal contains the device alarm characteristics. The server is configured to query the sensor and to send an alert to a remote terminal if the status flag signal indicates that the audio supervision signal matches the device alarm characteristics.

Abstract: An electronic stethoscope has a body with a diaphragm at one end of the body. A microphone is housed within the body, wherein the microphone is to generate a first analog audio signal based on sounds waves amplified by the diaphragm. A processing device is also housed within the body and connected to the microphone. The processing device is to receive a second audio signal from a computing device connected to the electronic stethoscope via a connection, and enable the microphone responsive to receipt of the second audio signal.

Abstract: An electronic stethoscope includes an acoustic sensor assembly having a first microphone to detect biological sounds within a body, a detection system in communication with the first microphone to receive an auscultation signal from the first microphone, the auscultation signal including information of the biological sounds detected by the first microphone. The stethoscope also includes a second microphone in communication with the detection system to detect noise from an environment of the body. The detection system receives a noise signal from the second microphone, and provides a resultant signal based on the auscultation signal and the noise signal. The detection system subtracts information from the auscultation signal to produce the resultant signal, where the subtracted information is based on the noise signal such that the subtracted information is based more on higher frequency ranges of the noise signal compared to a lower frequency range corresponding to the biological sounds.

Abstract: An acoustic sensor is configured to provide accurate and robust measurement of bodily sounds under a variety of conditions, such as in noisy environments or in situations in which stress, strain, or movement may be imparted onto a sensor with respect to a patient. Embodiments of the sensor provide a conformable electrical shielding, as well as improved acoustic and mechanical coupling between the sensor and the measurement site.

Abstract: An adapter system that converts an in-line microphone to a stethoscope is described. The adapter includes a grooved channel, a rear cap, a front diaphragm, a recessed surface and a sound tunnel. The grooved channel may be disposed in a base. The grooved channel receives the in-line microphone. The lid covers the grooved channel and the lid is removably coupled to the base. The front diaphragm contacts a listening surface. Also, the front diaphragm is coupled to the base. The recessed surface is disposed adjacent to the front diaphragm. The sound tunnel includes a sound tunnel entrance proximate to the recessed surface. The sound tunnel extends to the grooved channel. The recessed surface and the sound tunnel capture sound vibrations received at the front diaphragm and transmit the sound vibrations through the sound tunnel to the in-line microphone disposed in the grooved channel.

Abstract: Embodiments are directed to detecting the effect of external auditory sounds on a subject using a hands-free stethoscope, and further playing back those external auditory sounds as they are experienced inside a subject's body. A system is provided which includes a microphone that detects auditory sounds that are external to the system, and a stethoscope diaphragm that detects sound waves emitted within or as experienced in a subject's body. The stethoscope diaphragm also transfers a representation of those sound waves to a processor or to a headphone jack for playback. The processor of the system receives the representation of sound waves and also receives the detected external auditory sounds to determine what effect the detected external auditory sounds are having on the subject or on a second subject. The system also includes a communications module configured to communicate the results of the determination with other electronic devices.

Abstract: Provided is magnetic resonance imaging (MRI) acoustic system that includes a magnet that is included in a bore having an image-taking space where an object is able to be accommodated and that forms a magnetic field in the image-taking space to obtain an MR image of the object, an electro-acoustic transducer that is located outside of the bore, and includes coils through which a current for generating an attraction force or a repulsion force with respect to the magnetic field generated by the magnet and a vibrating plate that vibrates in response to the an attraction force or the repulsion force, and a controller that controls the intensity of the current inputted to the electro-acoustic transducer to generate a sound by using the magnetic field that is generated by the magnet.

Abstract: In a primary sound pressure-gradient type condenser microphone unit driving a diaphragm by difference in sound pressure applied to acoustic terminals in front and back of the diaphragm, a drive force of the diaphragm and sound collection characteristics in a high frequency band are easily adjusted. The condenser microphone unit includes a first pipe extending forward on the front side of a diaphragm and a second pipe arranged so as to surround the first pipe. A front acoustic terminal communicating with a front surface of the diaphragm is formed on an inner side of either one of the first pipe or the second pipe. A rear acoustic terminal communicating with a back surface of the diaphragm from the rear side of a fixed electrode is formed on an inner side of the other pipe.

Abstract: The present disclosure provides an earphone device with sound adjustment capability that allows a user to dynamically adjust sound acoustics resonating from the device. In one aspect, the earphone device includes a housing having an acoustic output port. The acoustic output port is adapted to receive an audio signal. In this regard, sound resonates from the acoustic output port based on the audio signal. The earphone device also includes a telescopic portion having a hollow tube portion attached to the housing. The hollow tube portion may be in communication with the acoustic output port. The telescopic portion is configured to receive a fitting member. The fitting member is configured to adjust a bass range of the outputted sound resonating from the acoustic output port by passing through the telescopic portion so as to adjust a length of the hollow tube portion.

Abstract: A Baby Monitoring Mat is provided having a top mesh layer, a bottom mesh layer, two flexible sheets, and an optical cable. The optical cable can be routed between the top mesh layer and the bottom mesh layer. The flexible sheets are also between the top mesh layer and the bottom mesh layer forming a sensing area. A light source is provided for feeding light from one side of the optical cable to a photodiode for detecting light attenuation at the other end of the optical cable. A processor receives signals from the light source and photodiode and the signals are processed to determine movements and breath counts. The signals are generated based on the light attenuation changes along the optical fiber cable detected by photodiode. A method for monitoring baby on a mat is also provided.

Abstract: A rugged, ergonomic integrated telecommunications handset includes an electronic controller that interoperates and controls the universal remote control (URC), which connects to multiple radios simultaneously. The controller downloads options which are implemented by the controller. The handset has an ability to vibrate in a silent mode, and has a memory capacity, as well as GPS capacity. Ergonomically, the handset has a pair of side arrays of protruding ribs, which enhance gripping, preventing the handset from falling out of the user's hands, even if the user has gloves on in inclement weather conditions in the field. While compatible with the latest radio system software defined dual net and dual channel radio equipment, the handset is also backward compatible with single radios or with two or more separate radios.

Abstract: A microphone device includes an audio signal output circuit that balanced-outputs, through a balanced transmission line, an audio signal output from a condenser microphone unit, a balanced output terminal including a hot terminal, a cold terminal, and a ground terminal connected to the balanced transmission line, a power supply circuit that supplies a phantom power supply to the audio output circuit from the balanced output terminal through the balanced transmission line, and a display circuit including light emitting elements that perform lighting and non-lighting according to an operation of a manual switch, and the display circuit includes constant current elements that generate a constant current through the balanced transmission line, a constant voltage element connected to the constant current elements and which generates a constant voltage, and light emitting elements connected to the constant current elements, and to which the constant voltage by the constant voltage element is applied.

Abstract: A wearable physiological acoustic sensor has an embedded and stacked acoustic sensing component architecture that inhibits motion-related impulse noise and environmental background noise, and provides good body sound capture, good patient comfort and an unobtrusive presence. The embedded and stacked component architecture also includes an environmental microphone that enables cancellation of background noise for further noise reduction.

Abstract: A stethoscope front-end recorder device (also referred to as Sleeve) for the chest piece of a stethoscope, which is easily installed and removed. The Sleeve is attached to the chest piece of a stethoscope for comprehensive diagnosis of heart issues. The Sleeve contains sensors for acquiring biosensor parameters such as electrocardiogram, body temperature, heartbeat, heart rhythm, heart rate variability, heart rate turbulence, heart sounds, respiration, cardiac index and blood flow. The Sleeve has Bluetooth interface communicating with a mobile device with software component, interfacing with a back-end server with the capability to capture, analyze and save patient information.

Abstract: An infrasonic stethoscope for monitoring physiological processes of a patient includes a microphone capable of detecting acoustic signals in the audible frequency bandwidth and in the infrasonic bandwidth (0.03 to 1000 Hertz), a body coupler attached to the body at a first opening in the microphone, a flexible tube attached to the body at a second opening in the microphone, and an earpiece attached to the flexible tube. The body coupler is capable of engagement with a patient to transmit sounds from the person, to the microphone and then to the earpiece.

Abstract: An earphone including at least one microphone, an analog pre-emphasis filter for pre-emphasis of the microphone signal, an AD-converter for digitizing the output signal of the pre-emphasis filter, an active noise compensation unit for performing active noise compensation based on the pre-emphasized and digitized output signal of the microphone and for outputting a counter sound signal, and a DA-converter for performing analog/digital conversion of the counter sound produced by the active noise compensation unit.

Abstract: Provided is a piezoelectric power generator that has an overall compact size and in which a plurality of piezoelectric elements having a low natural frequency of vibration and that generate a large amount of power can be arranged in a compact manner. A piezoelectric power generator includes a first and second piezoelectric elements, which each have a cantilever structure, fixed to the top of two opposing side walls of a housing. The first piezoelectric element and the second piezoelectric element are arranged so as to oppose each other in an alternating manner and respectively have a first weight and a second weight joined to free ends thereof. Unused spaces formed below the fixed end sides of the piezoelectric elements are used as spaces in which the weights can move by positioning one of the weights under the fixed end side of the other of the piezoelectric elements.

Abstract: A stethoscope front-end recorder device (also referred to as Sleeve) for the chest piece of a stethoscope, which is easily installed and removed. The Sleeve covers the circumference of the chest piece of a stethoscope. The Sleeve contains sensors for acquiring biosensor parameters such as electrocardiogram, body temperature, heartbeat, heart rhythm, heart rate variability, heart rate turbulence, heart sounds, respiration, cardiac index and blood flow. The Sleeve has Bluetooth interface communicating with a mobile device with software component, interfacing with a back-end server with the capability to capture, analyze and save patient information.

Abstract: A digital microphone, the microphone includes a microelectromechanical (MEMS) component and a frequency boost component. The MEMS component is configured to convert. sound into an electrical signal. The frequency boost component is configured to receive the electrical signal and ultrasonically boost the electrical signal to create a frequency response. The frequency response does not substantially affect an audio band of interest of the microphone.

Abstract: An acoustic sensor configured to non-invasively detect acoustic vibrations associated with a medical patient. The acoustic vibrations are indicative of one or more physiological parameters of the medical patient. The acoustic sensor can include a sensor support and at least one sound sensing membrane supported by the sensor support. The membrane can be configured to detect acoustic vibrations associated with a medical patient. The membrane may also be configured to produce a membrane signal corresponding to the acoustic vibrations when the acoustic sensor is attached to the medical patient. The acoustic sensor can also include a probe-off assembly supported by the sensor support. The probe-off assembly can be configured to produce a probe-off signal responsive to attachment of the acoustic sensor to the medical patient and detachment of the acoustic sensor from the medical patient.

Abstract: The present invention is an ambient noise canceling physiological acoustic monitoring system and method. The system and method utilizes a plurality of microphones to collect input data including ambient noise signals, bed frame noise signals and patient respiratory and cardiac data signals. The system and method cancels the ambient noise and bed frame noise signals, and calculates a filtered audio output signal with an algorithm that utilizes ECG rhythm patterns and impedance pneumography. The set of input data and the filtered audio output signal are then displayed in real time.

Abstract: An acoustic sensor is configured to provide accurate and robust measurement of bodily sounds under a variety of conditions, such as in noisy environments or in situations in which stress, strain, or movement may be imparted onto a sensor with respect to a patient. Embodiments of the sensor provide a conformable electrical shielding, as well as improved acoustic and mechanical coupling between the sensor and the measurement site.

Abstract: A noise cancellation device (NCD) comprises a microphone, an analog-to-digital converter, a digital-to-analog converter, a rechargeable battery, and a processor. The NCD acquires an audio input, from an external device such as a stethoscope or a cell phone, and passes the analog data into an ADC (analog-to-digital converter) for signal conversion. The digitized signals are then passed to the processor for further processing. The processor contains all the processing functions such as preprocessing (divide the input data into frames and apply shaping function to each frame), short term Fourier transform (STFT), adaptive filtering, inverse STFT, and signal synthesis.

Abstract: Disclosed herein, among other things, are apparatus and methods for micromachined ultrasonic transducer switches for hearing assistance devices. In various embodiments, a hearing assistance device includes a housing, hearing assistance electronics within the housing, and a micromachined ultrasonic transducer connected to the hearing assistance electronics. The micromachined ultrasonic transducer is configured to switch upon detection of proximity or touch by the wearer. In various embodiments, the micromachined ultrasonic transducer includes one ultrasonic transmitter and one ultrasonic receiver. The micromachined ultrasonic transducer is adapted to control one or more functions of the hearing assistance electronics, in various embodiments.

Abstract: A smart portable stethoscope is formed of a smart mobile device and a casing assembly for the mobile device. The casing assembly comprises a casing member, a diaphragm holder member configured to securely and effectively retain a diaphragm, and a vibrator-transducer member. The casing member includes a diaphragm connector part configured to securely fasten the diaphragm holder member to the casing member. The vibrator-transducer member is configured to be securely fastened to diaphragm holder member or casing member in such a manner that its vibrator is disposed to interconnect with the diaphragm and effectively duplicate vibrations captured by the diaphragm so as to deliver medical-grade auscultation electronic signal based on the duplicated vibrations to the mobile device through an audio plug plugged into a microphone jack thereof.

Abstract: A measuring device includes an audio collection module, an audio player module and a switch module. The audio player module electrically connects to the audio collection module, and the switch module electrically connects to the audio player module. The audio collection module collects sounds to generate an audio signal. The audio player module plays the audio signal. The switch module sets an enabling signal for controlling the audio player module. The enabling signal is set to be at either a first state or a second state different from the first state. When the enabling signal is at the first state, the audio player module plays the audio signal under a first output mode. When the enabling signal is at the second state, the audio player module plays the audio signal under a second output mode different from the first output mode.

Abstract: A mounting system is provided to allow the attachment of an acoustic collector to a handheld electronic device such that sound is conducted directly to the device's microphone. A fitted case or band encloses part of the device and includes a tube running from the collector to the device's microphone. In certain embodiments, the tube may be embedded in the case, and a detachable mount may be provided to connect the collector to the case. The collector may be a stethoscope chestpiece, or an open air collector, such as a parabolic collector.

Abstract: Provided is an electronic stethoscope pick-up head comprising an acousto-electrical transducer disposed in a chamber, the transducer being configured to generate an electrical signal representing acoustical vibrations, wherein the chamber further comprises a sound influencing bell defining a cavity to provide air communication between the transducer and a diaphragm attached to an outer end of the bell, wherein the diaphragm is acoustically decoupled from the transducer; and one or more ventilation air path as the only means to provide air communication between the cavity and outside of the chamber, wherein the air path is configured to restrict air flow through the air path.

Abstract: A device for converting acoustic data collected by a stethoscope into digital data for transmission to a processor for storage and/or comparison with data stored in a database, and to optionally provide computer generated suggestions for diagnosis, is provided in the form of an in-line device interposable between a head of the stethoscope and an acoustic transmission portion of the stethoscope, or is integral with the head, and advantageously has the appearance of an icon of pleasing appearance, for example, a butterfly, in which are incorporated the structural requisites of a functioning stethoscope and/or capabilities for receiving and transmitting to a diagnostician, audio signals gathered from patient examination, and optionally also other data collected at examination and/or following the examination. The butterfly-shaped device, includes a central body advantageously serving as a conduit for transmitting sound received from the patient to the physician or a remote system for analysis and diagnosis.

Abstract: A diagnostic system for collecting, processing, recording and analyzing sounds associated with the physiologic activities of various human organs. The system includes a plurality of transducers placed on the body surface at the operator's discretion. The transducers are coupled to analog/digital signal processing circuitry for enhancement of the desired signal and exclusion of ambient noise. An A/D converter digitizes the incoming data and transmits data, which is divided into a multitude of discrete blocks, received over very finite intervals of time, to a computer workstation and moved through an analysis program sequentially. The program is displayed as a series of icons which depict operations that the program performs and which allow the operator to reprogram the system at any time. The data is finally displayed in graphical format and stored in memory as the program processes each block sequentially.

Abstract: In some embodiments, an apparatus for acquiring, processing and transmitting physiological sounds may include a sensor for acquiring physiological sounds. Analog signals representative of the physiological sounds are converted into an electrical output. The electrical output is converted to digital data. A processing unit processes the digital data. The digital data is transmitted over a wireless network.

Abstract: An auscultation apparatus including an optical microphone is proposed. Optical microphones can reliably acquire sounds of the most disparate frequencies even in an environment permeated by electromagnetic fields, without influencing said fields. Such an optical microphone of an auscultation apparatus can be disposed inside a medical examination and diagnostic device during operation. Given a suitable arrangement, both the heart sounds and the respiratory sounds of a patient can be recorded and monitored already with just one optical microphone.

Abstract: A wireless electronic stethoscope device is disclosed. The wireless electronic stethoscope device includes a pen-shaped main body; a sensor module for data collection; a processor module to coordinate operation of electronic stethoscope modules; a wireless communication module to transmit and receive digital and analog data; a power module including a battery for storing energy; a control module to communicate information and receive operational commands.

Abstract: A portable ergonomic compact handheld stethoscope to aid in the listening of internal body sounds.

Abstract: According to certain described aspects, multiple acoustic sensing elements are employed in a variety of beneficial ways to provide improved physiological monitoring, among other advantages. In various embodiments, sensing elements can be advantageously employed in a single sensor package, in multiple sensor packages, and at a variety of other strategic locations in the monitoring environment. According to other aspects, to compensate for skin elasticity and attachment variability, an acoustic sensor support is provided that includes one or more pressure equalization pathways. The pathways can provide an air-flow channel from the cavity defined by the sensing elements and frame to the ambient air pressure.

Abstract: Provided is an electronic stethoscope pick-up head comprising an acousto-electrical transducer disposed in a chamber, the transducer being configured to generate an electrical signal representing acoustical vibrations, wherein the chamber further comprises a sound influencing bell defining a cavity to provide air communication between the transducer and a diaphragm attached to an outer end of the bell, wherein the diaphragm is acoustically decoupled from the transducer; and one or more ventilation air path as the only means to provide air communication between the cavity and outside of the chamber, wherein the air path is configured to restrict air flow through the air path.

Abstract: A stethoscope earplug seat and the fitting a fitted configuration with an earplug head thereof. The stethoscope earplug seat includes a large tubular body (6) and a small tubular body (5). The large tubular body (6) sheaths the outside of the small tubular body (5), and one side of the tube mouth of the large tubular body (6) is level with one side of the tube mouth of the small tubular body (5). The inside radius of the large tubular body (6) is equal to the outside radius of the small tubular body (5), the length of the large tubular body (6) is smaller than the length of the small tubular body (5), and the out-edge part of one side of the small tubular body (5) which is away from the large tubular body (6) is provided with an annular slot (7).

Abstract: An electronic stethoscope includes an acoustic sensor assembly having a plurality of microphones arranged in an acoustic coupler to provide a plurality of pick-up signals. The electronic stethoscope also includes a detection system to communicate with the acoustic sensor assembly and to combine the plurality of pick-up signals to provide a detection signal. The electronic stethoscope also includes an output system to communicate with the detection system. The acoustic coupler uses a compliant material that forms an acoustically tight seal with a body under observation.

Abstract: An electronic sound monitor for use as a stethoscope, a signal treatment and a method for treating the signals using the monitor. The sound monitor includes at least one transducer for transforming vibrations to electrical signals, a filtering, A/D- and D/A-converter, amplifier, a processor, a sound chamber in which at least one transducer for transforming electrical signals to sound is arranged, and a sound channel opening into the sound chamber. The sound channel being adapted to forward the sound from the sound chamber through an opening connecting the sound channel with the ambient air.