Active noise control (ANC), including active and adaptive noise cancellation (ANC) with non-voice-coil transducers having highly linear transfer functions, such as planar transducers, planar magnetic transducers, electro-static transducers, and piezo-electric transducers. This active and adaptive noise cancellation (ANC) may be used with: planar transducer headphones and earphones; open-backed and closed-back headphones and earphones; in-ear earphones, and phase plugs.

An electronic apparatus may include a loudspeaker that includes an enclosure; a first driver disposed in the enclosure and configured to output a sound based on an input audio signal; a unit accommodator having a hole in which the first driver is disposed, and extending toward an inside of the enclosure; a space forming portion extended from an outer edge of the unit accommodator, surrounding a back of the first driver to form a space with the unit accommodator, and spaced apart from an inner edge of the unit accommodator; a slot forming portion extending from the space forming portion, and having an inner surface spaced apart from an outer surface of the unit accommodator to form a first sound output passage; and a sound absorber disposed at at least one of the outer surface of the unit accommodator and the inner surface of the slot forming portion.

The present invention provides a MEMS microphone, including: a base with a back cavity; and an electric capacitance system arranged on the base. The electric capacitance system includes a back plate, a first diaphragm and a second diaphragm opposite to the back plate and arranged on an upper and lower sides of the back plate. The MEMS microphone further includes an insulation layer isolating the base, the back plate, the first diaphragm and the second diaphragm, and a sealing space formed between the first diaphragm and the second diaphragm. The pressure in the sealing space is equal to an external pressure.

Certain embodiments of the disclosure relate to microphone-equipped wearable devices, and more particularly, to wearable devices worn on users' ear. According to certain embodiments of the disclosure, a wearable device comprises a speaker, a microphone, and a housing, the housing includes a protrusion configured to be insertable into a user's ear, a first sound path including a first opening formed through an area of a surface of the protrusion, extending from the first opening in a first length, and including a second opening facing the speaker, and a second sound path including a third opening formed through another area of the surface of the protrusion, extending from the third opening in a second length larger than the first length, and including a fourth opening facing the microphone. Other certain embodiments are also possible.

A speaker apparatus includes an enclosure, a speaker unit, and a bass reinforcement unit. The enclosure includes an inner cavity, where a cavity volume of the inner cavity is in a range of 0.5 milliliter to 1 milliliter, the enclosure has a cavity acoustic compliance value, and the cavity acoustic compliance value is obtained by dividing the cavity volume by a product of air density and a sound velocity squared. The speaker unit includes a diaphragm and a surround, the speaker unit has a speaker acoustic compliance value and an effective sound outlet area, and the speaker acoustic compliance value is a product of a mechanical compliance value of the surround and the effective sound outlet area squared, and a ratio of the speaker acoustic compliance value to the cavity acoustic compliance value is less than or equal to 1. The bass reinforcement unit outputs a low-frequency response frequency.

A loudspeaker parameter system for vented box driver excursion modeling, may include a loudspeaker driver having a conductor, a magnet and a diaphragm. The system may further include a processor for excursion modeling configured to receive an input signal, determine a voltage level of the input signal, an enclosure having a resonant port, estimate port parameters including at least one of an acoustic resistance or acoustic mass, and apply a voltage limit based on the vented box excursion model utilizing the port parameters.

An acoustic sensor has a semiconductor substrate having an opening, a back plate that is disposed facing the opening of the semiconductor substrate, that is configured to function as a fixed electrode, and that has sound holes that allow passage of air, a vibration electrode film disposed facing the back plate through a void, and a casing configured to house the substrate, the back plate, and the vibration electrode film, and having a pressure hole that allows inflow of air. The acoustic sensor converts transformation of the vibration electrode film into a change in capacitance between the vibration electrode film and the back plate to detect sound pressure.

A MEMS microphone includes a substrate defining a cavity including a first sidewall extending a vertical direction, a back plate disposed over the substrate and defining a plurality of acoustic holes, a diaphragm disposed between the substrate and the back plate, the diaphragm having at least one vent hole, an anchor extending from a circumference of the diaphragm to connect an end portion of the diaphragm to an upper surface of the substrate, and at least one path member communicating with the vent hole, the path member providing a flow path for the acoustic pressure to flow downwardly toward the cavity.

A novel loudspeaker with a reflex enclosure that has the reflex port terminating to the bottom of the enclosure. The loudspeaker further includes a stand which is removably attached to the bottom of the enclosure so as to create a clearance between the bottom and the surface supporting the loudspeaker.

A personal audio system enabling a user to distinguish approximate locations of sound sources comprises at least one sound receiver. The sound receiver comprises a sound collecting structure for collecting sound. The sound collecting structure comprises a plurality of sound passages opening toward different directions and with different sizes to collect sound waves from the environment. The different sizes of the openings render a decline or an increase in specific frequency ranges of sound as a result of different resonances via the different openings. The user may therefore distinguish the direction of a sound source based on the slightly different pitches (frequencies) of the sound.