A magnetic motor device of an electrodynamic transducer, which includes a bonded annular magnet and a tubular element mounted coaxially relative to the bonded annular magnet. The bonded annular magnet includes a magnetic cylindrical surface, while the tubular element includes a winding extending opposite the magnetic cylindrical surface, the tubular element configured to be driven axially relative to the bonded angular magnet when electric power is supplied to the winding. A metal tubular member includes a metal cylindrical surface, and the metal tubular member is mounted coaxially relative to the tubular element such that the metal cylindrical surface extends opposite the magnetic cylindrical surface relative to the winding.

A transducer including a driven element and a magnet assembly. The magnet assembly is coupled to the driven element and includes a first, second and third magnet. Each of the magnets have a first and second magnetic pole. The first magnetic pole of the first magnet and the first magnetic pole of the second magnet being proximate to each other and facing each other thereby defining a magnetic zone therebetween. The second magnetic pole of the third magnet being magnetically proximate to said magnetic zone. The first magnetic poles all having the same polarity, and the second magnetic poles all having the same polarity.

An electromechanical transducer including a magnetic circuit having a magnet configured to generate a magnetic field and a magnetic gap into which a voice coil associated with a diaphragm is at least partially inserted, the magnetic field having a primary flux component and a secondary flux component. The transducer further including a housing positioned around the magnetic circuit, the housing having an acoustic spout whose sound outlet opening is positioned outside of a portion of the magnetic field that is dominated by the primary flux component. A transducer including an enclosure having a top wall, a bottom wall, at least one side wall connecting the top wall to the bottom wall and an acoustic spout extending from the top wall or the bottom wall, a diaphragm, a voice coil and a magnet assembly having a ring magnet and a gap within which the voice coil is positioned.

An apparatus including a frame; a coil movably connected to the frame; and a magnet system connected to the frame. The magnet system includes at least one magnet and at least one pole piece connected to the at least one magnet. The at least one pole piece include a magnet pot. A cross sectional length of the magnet pot and the frame are substantially the same in at least one cross sectional location.

A speaker control device in one embodiment includes a time to digital converter connected to a drive power source in series with a drive circuit for driving a plurality of coils of a speaker, the converter outputting a digital data in accordance with a voltage of the drive power source, and a monitor circuit detecting a state of the plurality of coils of the speaker based on digital data output by the time to digital converter.

A magnetic field transmitter, especially a transmitter used in conjunction with wireless communications earplugs. In one embodiment, a plate of magnetic material is used behind a coil of electrical conductor to improve the efficiency of the transmitter and to provide electrical and magnetic shielding. The specific dimensions and characteristics of the preferred embodiment of the transmitter described herein provide for efficient wireless communications.

A bone conduction device configured to couple to an abutment of an anchor system anchored to a recipient's skull. The bone conduction device includes a vibrating electromagnetic actuator configured to vibrate in response to sound signals received by the bone conduction device, and a coupling apparatus configured to attach the bone conduction device to the abutment so as to impart to the recipient's skull vibrations generated by the vibrating electromagnetic actuator. The vibrating electromagnetic actuator includes a bobbin assembly and a counterweight assembly. Two axial air gaps are located between the bobbin assembly and the counterweight assembly and two radial air gaps are located between the bobbin assembly and the counterweight assembly. No substantial amount of the dynamic magnetic flux passes through the radial air gaps.

An apparatus including a frame; a coil movably connected to the frame; and a magnet system connected to the frame. The magnet system includes at least one magnet and at least one pole piece connected to the at least one magnet. The at least one pole piece include a magnet pot. A cross sectional length of the magnet pot and the frame are substantially the same in at least one cross sectional location.

An audio speaker having a magnetic system that includes a magnetic insert in a recess of a bottom plate, is disclosed. More particularly, embodiments of the magnetic system include a magnetic insert having a higher magnetic saturation level than the bottom plate. Other embodiments are also described and claimed.

A transducer including a driven element and a magnet assembly. The magnet assembly is coupled to the driven element and includes a first, second and third magnet. Each of the magnets have a first and second magnetic pole. The first magnetic pole of the first magnet and the first magnetic pole of the second magnet being proximate to each other and facing each other thereby defining a magnetic zone therebetween. The second magnetic pole of the third magnet being magnetically proximate to said magnetic zone. The first magnetic poles all having the same polarity, and the second magnetic poles all having the same polarity.