An echo reducer includes: an obtainer configured to obtain frequency characteristics of a transmission system from a sound emitter of a sound emission and collection device to a sound collector of the sound emission and collection device; a determiner configured to determine whether or not both a transmission signal and a reception signal in the sound emission and collection device are in a state of including a sound; and an attenuator configured to attenuate the reception signal to be output to the sound emitter, by attenuation characteristics corresponding to the frequency characteristics of the transmission system that the obtainer obtains, when the determiner determines that both the transmission signal and the reception signal in the sound emission and collection device include a sound.

There is provided a speaker device 1 having a speaker unit 10 and an enclosure 30 in which a plurality of rod-shaped bodies 31 is integrally bonded to each other and which is arranged in a space behind the speaker unit 10. Thus, a sound wave output from the speaker unit 10 to the rear side thereof can be more effectively damped.

According to the present invention, an apparatus, a signal processing unit, data, a processing apparatus, a sound converter, a software product and a method are proposed. The apparatus is proposed for acoustic reproduction, wherein the apparatus is provided with a first electroacoustic sound transducer for generating a sound field, the first electroacoustic sound transducer having an input for receiving an electrical signal for generating the corresponding sound field, wherein the apparatus is characterized in that also a device is provided which is configured to enter into an acoustic interaction with the generated sound field of the first electroacoustic sound transducer in order to generate a modified sound field and wherein the modified sound field has a predetermined acoustic impedance value.

A microphone transducer is provided, the microphone transducer comprising a housing and a transducer assembly supported within the housing and defining an internal acoustic space. The transducer assembly includes a magnet assembly, a diaphragm disposed adjacent the magnet assembly and having a front surface and a rear surface, and a coil attached to the rear surface of the diaphragm and capable of moving relative to the magnet assembly in response to acoustic waves impinging on the front surface. The transducer assembly further includes a primary port establishing acoustic communication between the internal acoustic space and an external cavity at least partially within the housing, and a secondary port located at the front surface of the diaphragm.

A personal listening device including at least one direct-radiating balanced-armature audio transducer and at least one substantially enclosed, indirect-radiating, or tube-coupled balanced-armature transducer. The tube-connected transducer emits sound waves which pass through a hole, slot, tube or bore before entering an airspace near the eardrum of a user, while the direct-radiating transducer emits sound waves directly into the airspace adjacent the indirect-radiating transducer or tube, which airspace is contiguous with the airspace near the eardrum of the user.

An in-ear receiver can be used in a headset and/or hearing aid and includes a housing in which at least one ear canal section is configured to be inserted into an ear canal of a wearer when the in-ear receiver is used as intended. The housing defines at least one outer contour that is configured with at least in one section adapted to the ear canal of the wearer. The in-ear receiver includes a sound transducer arranged in the housing, and at least one resonant cavity, which is formed in the housing and is divided by the sound transducer into a front volume and a rear volume. The sound transducer is a MEMS sound transducer, and the front volume and/or the rear volume have/has an inner contour adapted to the ear canal.

A camera includes one or more microphone pairs. A first microphone (e.g., a main microphone) is ported to the outside of the camera and captures the desired external audio signal, but may also capture undesired vibrational noise. A second microphone has a similar structure to the first microphone, but is not ported to the outside of the camera. Instead, the second microphone is ported into an enclosed cavity (e.g., 1-2 cubic centimeters in volume). The second microphone may pick up the same vibration excitation and internal acoustic noise as the first microphone but very little of the desired external acoustic sounds around the camera. The unwanted noise can then be removed by subtracting the second audio signal from the second microphone from the main audio signal from the main microphone.

This application describes a noise reduction apparatus (800) for a microphone device (100) having an acoustic port (110). The apparatus has a spectrum peak detect block (301) for receiving a microphone signal (S.sub.MIC) and determining, from the microphone signal, at least one characteristic of a resonance peak (202) associated with the acoustic port of the microphone. The at least one characteristic may comprise a resonance frequency (f.sub.H) and/or quality factor (Q.sub.H). A noise reduction block (801) is configured to process the microphone signal based on the resonance characteristic so as to reduce noise in the processed microphone signal due to said resonance. The noise reduction block may apply a function which is the inverse of the determined resonance characteristic.

A speaker apparatus includes a sound guide and a pair of speakers mounted to the sound guide. The sound guide includes a first guide portion configured to guide a sound generated from any one of the pair of speakers in a first direction; and a second guide portion configured to guide a sound generated from the other speaker in a second direction that is plane-symmetric with respect to the first direction. Each of the first and second guide portions includes an opening forming portion formed in an end portion of the corresponding portion and including an opening configured to output a sound generated by the pair of speakers, and a slit forming portion including a slit configured to output a sound, together with the opening, wherein the slit is extended from one side of the opening.

A moving coil speaker may comprise a frame, a magnet assembly fixedly mounted to the frame and having a central axis, first and second annular gaps defined by the magnet assembly and concentrically disposed about the central axis, a voice coil at least partially received within the first annular gap, a cone coupled to and driven by the voice coil, a secondary coil at least partially received within the second annular gap, and a mass coupled to and driven by the secondary coil. When variable electrical audio signals are sent from an audio signal source respectively through the voice coil and the secondary coil, the coils and their respectively associated cone and mass reciprocate back and forth in opposite axial directions, with the reciprocal movement of the cone being counterbalanced by the reciprocal movement of the mass.