Disclosed is a mid-range speaker. The operating range of the mid-range speaker can extend to 20 KHz, and the speaker has an improved high-frequency directivity. A mid-range speaker, comprising a basket, a diaphragm arranged on the basket, a magnetic circuit system arranged on the basket, and a voice coil connected to the diaphragm, wherein the diaphragm comprises a cellular board having a front face and a back face, and covering films respectively covering the front face and the back face of the cellular board; and the cellular board is provided with a plurality of holes.

The present invention relates to a transducer device comprising: At least one dielectric electro-active membrane, an actuation element coupled with the at least one electro-active membrane so that the electro-active membrane is biased in at least one of its plane directions;
wherein the actuation element is provided with a mass so that when electrically excited a first resonance frequency is developed in a fundamental mode of a longitudinal oscillation of the actuation element and a second resonance frequency is developed in a fundamental mode of a transverse oscillation of the membrane, wherein the second resonance frequency is at least six times higher than the first resonance frequency.

The present disclosure provides a speaker diaphragm and a speaker. The diaphragm includes two surface layers compounded together and at least one intermediate layer located between the two surface layers, at least one of the surface layers being a thermoplastic polyester elastomer film layer (11), at least one intermediate layers being an adhesive layer (12), wherein the plastic polyester elastomer is a copolymer composed of a hard segment A of polyester and a soft segment B of polyether or aliphatic polyester, and the hard segment A of polyester has a mass percentage of 10-95%. The speaker diaphragm accommodates an excellent rigidity, a good damping performance and resilience and so on.

An air-pulse generating device includes a film structure including a flap pair. The film structure is actuated to perform a common mode movement, so as to form an amplitude-modulated ultrasonic air pressure variation with an ultrasonic carrier frequency. The film structure is actuated to perform a differential mode movement, so as to form an opening at a rate synchronous with the ultrasonic carrier frequency. The air-pulse generating device produces a plurality of air pulses according to the amplitude-modulated ultrasonic air pressure variation.

A diaphragm assembly for a miniature acoustical transducer having a sufficiently light paddle to allow good audio performance and a sufficiently stiff frame to allow handling. The paddle may be made of a thin sheet of aluminium and the frame of thicker aluminium or a bent sheet of aluminium.

Provided is an energy harvesting system, including: a first electrode; a second electrode; a non-metalized mono-charged electret diaphragm disposed between the first and second electrodes; a base; a spring extending between the base and the electret diaphragm; and a rod in communication with the electret diaphragm and for manipulating a position of the electret diaphragm relative to the first and second electrodes.

A speaker comprises a housing having an opening; a waterproof sound-transmission membrane disposed on the housing to cover the opening of the housing; a speaker unit housed in the housing, the speaker unit comprising a speaker having a diaphragm; and an annular polymer membrane disposed between the diaphragm and the waterproof sound-transmission membrane, the annular polymer membrane comprising a through-opening in a radial direction with respect to the annular polymer membrane.

An earplug includes a housing and a receiver positioned in the housing. The receiver may be configured to receive a wireless audio signal from an audio source external to the earplug and convert the wireless audio signal to an electrical audio signal. The earplug may include a speaker configured to receive electrical audio signal from the receiver and convert the electrical audio signal into audible sound output from a speaker port. The earplug may include a projection including an opening that defines at least a portion of a sound channel from the speaker. The projection may receive the audible sound output from the speaker and output the audible sound out of the earplug. The earplug may include earplug padding configured to form a seal with a user's ear canal. The earplug may include an acoustic vent positioned in the sound channel, including a waterproof membrane extending across the channel.

A micro speaker capable of preventing voice coil rubbing, including an outer casing provided with a holding space, a diaphragm installed within the holding space, a magnet provided with an axis, a voice coil encircling the exterior of the magnet and connected to a diaphragm, and an elastic connecting member connected between the voice coil and the magnet. The diaphragm is disposed on the first end, and the magnet is disposed on the second end of the holding space so as to be separated from the diaphragm. The elastic connecting member is used to maintain a clearance between the voice coil and the magnet. After a signal voltage is fed into the voice coil, the diaphragm extends along the axis causing amplitudes of vibration, and the elastic connecting member reduces amplitudes of deflection produced along the axis, thereby preventing rubbing between the voice coil and the magnet from occurring.

Proposed is a vibration sensor including: a substrate; a first electrode positioned on the substrate; a support positioned on the first electrode and including a cylindrical hollow hole; and a diaphragm including a thin film positioned on the support and a second electrode positioned on the thin film. According to the present disclosure, it is possible to manufacture a skin-attachable vibration sensor that is attached to a user's neck to detect vibration acceleration in user's neck skin, thus exhibiting a uniform and high sensitivity to a user's voice over the frequency range of the human voice. In addition, the sensor sensitively detects a user's voice through neck skin vibrations rather than through air, thus being free from the influence of external noise or wind, and can recognize the user's voice even in a situation where a user's mouth is covered.