A method, system and devices to selectively control modal vibrations in an elastic panel with a number of force actuators distributed throughout the surface of the elastic panel to excite/depress the response of one or more vibrational resonant modes included in a prescribed subset. The force actuators are disposed such that prescribed modal excitation/depression may be realized when the actuators are driven by a common source signal.

A method of forming a device having a compliant member includes providing an elastomeric layer in an uncured state. The elastomeric layer is pre-cured to increase its viscosity. Subsequently, a bobbin and housing, each having an end, can be positioned such that their ends extend at least partially into the elastomeric layer. The elastomeric layer is cured to secure it to the bobbin housing. Examples of pre-cure and cure operations include one or more of a thermal cure, evaporative cure and ultraviolet cure, and the application of moisture, microwave energy and chemical additive. Due to the increased viscosity after the pre-cure, the migration of elastomeric material is substantially reduced relative to an uncured elastomeric material. The reduction in elastomeric material migration results in smaller menisci formed along the walls of the housing and bobbin, and reduced thinning of the compliant member formed at their ends.

A dipole loudspeaker for producing sound at bass frequencies. The dipole loudspeaker includes: a diaphragm having a first radiating surface and a second radiating surface, wherein the first radiating surface and the second radiating surface are located on opposite faces of the diaphragm; a drive unit configured to move the diaphragm at bass frequencies such that the first and second radiating surfaces produce sound at bass frequencies, wherein the sound produced by the first radiating surface is in antiphase with sound produced by the second radiating surface; a frame, wherein the diaphragm is suspended from the frame via one or more suspension elements, wherein the frame is configured to allow sound produced by the first radiating surface to propagate out from a first side of the dipole loudspeaker and to allow sound produced by the second radiating surface to propagate out from a second side of the dipole loudspeaker. The diaphragm includes a region of porous material having a specific airflow resistance in the range 5-5000 Pa.Math.s/m, wherein the diaphragm is configured to permit airflow through at least part of said region of porous material from the first radiating surface of the diaphragm to the second radiating surface of the diaphragm.

A loudspeaker for producing sound at bass frequencies including: a diaphragm; a frame, wherein a proximal end of the diaphragm is suspended from the frame by at least one proximal suspension element, wherein the at least one proximal suspension element is configured to substantially prevent translational movement of the proximal end of the diaphragm relative to the frame, whilst permitting translational movement of a distal end of the diaphragm which is opposite to the proximal end of the diaphragm; a drive unit configured to move the distal end of the diaphragm based on an electrical signal.

A method of forming a device having a compliant member includes providing an elastomeric layer in an uncured state. The elastomeric layer is pre-cured to increase its viscosity. Subsequently, a bobbin and housing, each having an end, can be positioned such that their ends extend at least partially into the elastomeric layer. The elastomeric layer is cured to secure it to the bobbin housing. Examples of pre-cure and cure operations include one or more of a thermal cure, evaporative cure and ultraviolet cure, and the application of moisture, microwave energy and chemical additive. Due to the increased viscosity after the pre-cure, the migration of elastomeric material is substantially reduced relative to an uncured elastomeric material. The reduction in elastomeric material migration results in smaller menisci formed along the walls of the housing and bobbin, and reduced thinning of the compliant member formed at their ends.

Provided in the present disclosure is a diaphragm, comprising a diaphragm body, wherein the diaphragm body comprises a fixing portion at an outer side, a bendable ring portion provided protruding from an inner ring side of the fixing portion and elastically bendable, and an inner side portion at an inner ring side of the bendable ring portion, the diaphragm body is made of a waterproof and breathable material having waterproof and breathable micropores. According to the present disclosure, the diaphragm body is made of waterproof and breathable material having waterproof and breathable micropores so that the diaphragm body has micropores, and the sizes of the micropores are between the size of water molecules and the size of air molecules, such that air molecules can smoothly pass through the diaphragm, while the water molecules can be effectively prevented from passing therethrough.

A dynamic loudspeaker driver comprising a magnet-system; a membrane; the membrane being movably mounted with respect to the magnet-system; at least one voice coil attached to the membrane and operatively coupled with the magnet-system, wherein the voice coil comprises an upper edge facing the membrane and a lower edge being arranged opposite the upper edge of the voice coil; at least one voice coil extension element comprising an upper surface facing the membrane and a lower surface facing the upper edge of the voice coil, wherein the lower surface of the voice coil extension element is attached the upper edge of the voice coil while the upper surface of the voice coil extension element is attached to the membrane.

A method of forming a device having a compliant member includes providing an elastomeric layer in an uncured state. The elastomeric layer is pre-cured to increase its viscosity. Subsequently, a bobbin and housing, each having an end, can be positioned such that their ends extend at least partially into the elastomeric layer. The elastomeric layer is cured to secure it to the bobbin housing. Examples of pre-cure and cure operations include one or more of a thermal cure, evaporative cure and ultraviolet cure, and the application of moisture, microwave energy and chemical additive. Due to the increased viscosity after the pre-cure, the migration of elastomeric material is substantially reduced relative to an uncured elastomeric material. The reduction in elastomeric material migration results in smaller menisci formed along the walls of the housing and bobbin, and reduced thinning of the compliant member formed at their ends.

The present invention provides a diaphragm structure of a sounding apparatus comprising: a thin-film layer; a first circuit thin-film layer fixed on a first side of the thin-film layer by means of a first electrolytic bonding layer; a second circuit thin-film layer fixed on a second side of the thin-film layer by means of a second electrolytic bonding layer; multiple holes passing through the first circuit thin-film layer, the thin-film layer and the second circuit thin-film layer; and multiple conductive layers disposed on inner circumferential walls of the holes and in contact with the first circuit thin-film layer and the second circuit thin-film layer. In the diaphragm structure provided by the present invention, instead of using back adhesives, electrolytic bonding is used to fix the circuit thin-film layers on two sides of a thin-film layer, thereby greatly reducing the thickness of the diaphragm structure.

A transducer unit for a MEMS sound transducer includes a support, a transducer element connected to the support and deflectable along a reciprocation axis, a coupling element for connecting the transducer element to a diaphragm in a manner spaced apart from the transducer element, and a spring region formed between the transducer element and the coupling element, the spring region including at least one spring element, which movably connects the transducer element to the coupling element, and which includes a damping layer, which at least partially covers the spring element.