The invention relates to audio transducer technology, including audio tuning systems to be utilised in personal audio devices, such as headphone, earphones, mobile phones and the like. The audio tuning system optimises the frequency response of the personal audio device by using Diffuse Field curve characteristics. The audio transducers of the personal audio device incorporate low resonance designs, including low resonance transducer and diaphragm suspensions to further optimise the sound quality of the device. The invention also relates to an audio transducer diaphragm construction that includes a three-dimensional lattice which may be utilised in any audio transducer application.

A loudspeaker device includes: a magnetic circuit that includes a yoke, a magnet, and a top plate; a voice coil body; a diaphragm; and a frame that holds the yoke and the diaphragm. The frame includes a through hole that holds the yoke at a predetermined position with the yoke being inserted into the through hole. The yoke includes a protrusion portion that abuts an outer peripheral surface portion of the frame that defines the through hole, with the magnetic gap being inside the frame.

A piezoelectric transducer comprises a deflectable structure having a first portion and a laterally adjoining second portion. The first portion has a piezoelectric layer and the second portion has an insulating material layer, and the second portion has a higher rigidity and a smaller mass per unit area than the first portion.

A speaker device includes: a diaphragm that radiates sound; an edge arranged in an outer periphery of the diaphragm; an attachment part facing an outer peripheral region of the edge; and a connecting member held between the outer peripheral region of the edge and the attachment part. The edge has a curved portion that is convexly curved to an opposite side to a side facing the connecting member.

A speaker device includes: a diaphragm that radiates sound; an edge arranged in an outer periphery of the diaphragm; an attachment part facing an outer peripheral region of the edge; and a connecting member held between the outer peripheral region of the edge and the attachment part. The edge has a curved portion that is convexly curved to an opposite side to a side facing the connecting member.

A diaphragm has a configuration including a diaphragm main body, a cone part on an outer periphery of the diaphragm main body, a ring member joined to the cone part, and an edge having an inner periphery joined to an outer periphery of the ring member or an outer periphery of the cone part. This configuration improves the rigidity without changing the shape of the diaphragm main body, that is, without giving rise to a mass increase in the diaphragm main body, and keeps the sound pressure from decreasing in a high frequency range.

A dipole speaker assembly comprises a transducer section, a front volume section, and a rear volume section. The transducer section includes a frame and piezoelectric actuators coupled to the frame. The piezoelectric actuators are configured to generate an acoustic pressure wave. The transducer section includes a first side and a second side, the second side being opposite the first side. The front volume section is coupled to the first side to form a front cavity, the front volume section including an aperture from which the generated acoustic pressure wave exits the front volume section towards an ear canal of a user. The rear volume section is coupled to the second side to form a rear cavity. The generated acoustic pressure wave exiting the rear volume section cancels the generated acoustic pressure wave exiting the front volume section in the far field.

Provided is a piezoelectric film capable of realizing an electroacoustic conversion film with an excellent heat dissipation property, in which a sufficient sound pressure with respect to an input operating voltage is obtained. The piezoelectric film is a piezoelectric film including a polymer-based piezoelectric composite material which contains piezoelectric particles in a matrix containing a polymer material, electrode layers which are laminated on both surfaces of the polymer-based piezoelectric composite material, and a protective layer laminated on a surface of at least one electrode layer, in which in a case where a cross section of the piezoelectric film is observed with a scanning electron microscope, at least one electrode layer has a plurality of projections directed toward the protective layer, and the number of projections is in a range of 2 to 40 per visual field of 85 μm in the cross section.

A loudspeaker including a magnetic circuit; a voice coil body; a diaphragm attached to the voice coil body; a housing which accommodates the magnetic circuit and the voice coil body and to which an outer circumferential portion of the diaphragm and the magnetic circuit are attached; two connection terminals disposed exposed inside and outside the housing; and signal wires which extend from the voice coil body and are connected to the connection terminals. Each signal wire is outwardly curved to be away from a virtual straight line connecting the proximal end of the signal wire and the connection portion. The distal end of the signal wire projects from the connection portion toward the voice coil body.

The present invention discloses a speaker, which includes a basket, a vibration system fixed to the basket, and a magnetic circuit system arranged in the basket. The vibration system includes a first diaphragm fixed to the basket and a second diaphragm oppositely separated from the first diaphragm, the magnetic circuit system includes an upper clamping plate fixed to the basket, and the upper clamping plate is disposed separately from the second diaphragm. The upper clamping plate includes a fixing portion fixed to the basket, the upper clamping plate is provided with a step recessed towards the first diaphragm from one side of the upper clamping plate facing away from the first diaphragm, and the step is connected with the fixing portion.