A method for producing an ultrasonic transducer including an arrangement determination step of determining an arrangement of piezoelectric elements in a stack on the basis of mechanical quality factors of the respective piezoelectric elements; and an assembly step of assembling the stack in which the piezoelectric elements are arranged according to the arrangement determined in the arrangement determination step, a horn, and a back mass. In the arrangement determination step, the arrangement of the piezoelectric elements is determined so that the difference in mechanical quality factor between the piezoelectric elements adjacent in the longitudinal direction is within 5% of a mean value of the mechanical quality factors of the piezoelectric elements.

Disclosed are a directional acoustic sensor, a method of adjusting directional characteristics using the directional acoustic sensor, and a method of attenuating an acoustic signal in a specific direction using the directional acoustic sensor. The directional acoustic sensor includes a plurality of resonance units arranged to have different directionalities and a signal processor configured to adjust directional characteristics by calculating at least one of a sum of and a difference between outputs of the resonance units. In this state, the signal processor attenuates an acoustic signal in a specific direction by using a plurality of directional characteristics obtained by calculating at least one of the sum of and the difference between the outputs of the resonance units at a certain ratio.

An electronic device may include: a memory; a sound sensor; and a processor, wherein the processor is configured to: receive, from the sound sensor, sound data including a first piece of data corresponding to a first frequency band and a second piece of data corresponding to a second frequency band different from the first frequency band; receive voice data related to a voice of a registered user from the memory; perform voice identification by comparing the first piece of data and the second piece of data with the voice data related to the voice of the registered user; and determine an output based on a result of the voice identification.

An electronic device is provided with a main surface member which is used as a vibrating plate, a case which supports the main surface member and a sound generating unit which is attached to the case to generate sound by vibrating the main surface member. The sound generating unit is provided with a piezoelectric plate and a protective member. The piezoelectric plate has a longitudinal direction in a first horizontal direction and has an upper surface, a lower surface and a plurality of side surfaces. The protective member has a supporting portion covering the lower surface of the piezoelectric plate and supporting the piezoelectric plate, a protective portion provided to the supporting portion to cover at least one of the side surfaces of the piezoelectric plate and an attached portion attached to the case.

Systems and methods for a transducer assembly for a vehicle having a resonating surface. The transducer assembly comprising a housing, a spacer connected to the housing, and a piezoelectric assembly disposed between the spacer and the housing. The spacer is configured to connect to the resonating surface to form an air gap between the resonating surface and the piezoelectric assembly.

Systems and methods for a transducer assembly for a vehicle having a resonating surface. The transducer assembly comprising a housing, a spacer connected to the housing, and a piezoelectric assembly disposed between the spacer and the housing. The spacer is configured to connect to the resonating surface to form an air gap between the resonating surface and the piezoelectric assembly.

Sound signal processing apparatuses and methods of operating the same are provided. The sound signal processing apparatus includes: a band separator configured to separate sound signals into frequency bands; an adder configured to add sound signals; and a signal processor that is arranged between the band separator and the adder and comprises a plurality of signal processing blocks. The band separator includes elements for separating the sound signals into frequency bands, and the elements correspond one to one to the signal processing blocks.

A bone conduction speaker is provided. The bone conduction speaker includes: a housing forming an exterior; a stator including a pole piece fitted to a bottom of the housing and a voice coil arranged to an outer circumference of the pole piece; a vibrator including a permanent magnet mounted concentrically with the pole piece and voice coil, with an air gap from the pole piece, a weight attached to the permanent magnet to increase a vibration force, and a yoke attached to the permanent magnet and weight; a flexible printed circuit board mounted on the bottom of the housing, part of which extends out of the housing, and configured to transmit a signal to the voice coil; and a bone conduction pad attached to an outer surface of the housing. The vibration of the vibrator is transmitted to a bone of a user through the housing and bone conduction pad.

A bone conduction speaker is provided. The bone conduction speaker includes: a housing forming an exterior; a stator including a pole piece fitted to a bottom of the housing and a voice coil arranged to an outer circumference of the pole piece; a vibrator including a permanent magnet mounted concentrically with the pole piece and voice coil, with an air gap from the pole piece, a weight attached to the permanent magnet to increase a vibration force, and a yoke attached to the permanent magnet and weight; a flexible printed circuit board mounted on the bottom of the housing, part of which extends out of the housing, and configured to transmit a signal to the voice coil; and a bone conduction pad attached to an outer surface of the housing. The vibration of the vibrator is transmitted to a bone of a user through the housing and bone conduction pad.

An acoustic wave device includes a cover portion, an outer support layer, a support portion, a piezoelectric substrate, and functional elements on the piezoelectric substrate. The outer support layer is on the piezoelectric substrate around a region where the functional elements are disposed. The cover portion is opposed to the piezoelectric substrate with the outer support layer interposed therebetween. The support portion is in a hollow space defined by the piezoelectric substrate, the outer support layer, and the cover portion. The height of the support portion is smaller than that of the outer support layer and larger than that of each of the functional elements. A gap is provided between the support portion and the cover portion or between the support portion and the piezoelectric substrate.