Abstract: An electrodynamic actuator for a speaker or an electrodynamic acoustic transducer in general is disclosed, which comprises at least one voice coil, a magnet system and an arm arrangement of a plurality of arms connecting the at least one voice coil and the magnet system or at least a movable part thereof so that a relative movement between these parts is allowed. The arms are made of a metal core, which at least partly is coated with a coating structure having at least one coating metal layer consisting of a different material than the metal core.

Abstract: An electrodynamic actuator for a speaker or an electrodynamic acoustic transducer in general is disclosed, which comprises at least one voice coil, a magnet system and an arm arrangement of a plurality of arms connecting the at least one voice coil and the magnet system or at least a movable part thereof so that a relative movement between these parts is allowed. The arms are made of metal with a fatigue strength of at least 370 N/mm2 or an ultimate tensile strength of at least 1100 N/mm2.

Abstract: An electrodynamic actuator for a speaker or an electrodynamic acoustic transducer in general is disclosed, which comprises at least one voice coil, a magnet system and an arm arrangement of a plurality of arms connecting the at least one voice coil and the magnet system or at least a movable part thereof so that a relative movement between these parts is allowed. The arms are made of metal with a fatigue strength of at least 370 N/mm2 or an ultimate tensile strength of at least 1100 N/mm2.

Abstract: An electrodynamic actuator for a speaker or an electrodynamic acoustic transducer in general is disclosed, which comprises at least one voice coil, a magnet system and an arm arrangement of a plurality of arms connecting the at least one voice coil and the magnet system or at least a movable part thereof so that a relative movement between these parts is allowed. The arms are made of a metal core, which at least partly is coated with a coating structure having at least one coating metal layer consisting of a different material than the metal core.

Abstract: 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.

Abstract: 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.

Abstract: A speaker including a single coil for both normal voice and for creating an HAC field. A large coil may be provided in combination with a strong magnet. The components of the speaker may be designed so as to maximize the space available for the voice coil and for the magnet.

Abstract: A loudspeaker in which a magnetic particle filter is provided in the vicinity of a sound outlet port.

Abstract: A loudspeaker in which a magnetic particle filter is provided in the vicinity of a sound outlet port.

Abstract: A headbox in a paper machine, which headbox has a stock outlet for a jet of stock having a specific length, angle of impact and point of encounter in relation to a nip in the wet section of the paper machine, which headbox has two stand parts, lifting arms with front and rear journalling means and a device for setting the position and alignment of the headbox so that the stock jet obtains said specific length, angle of impact and point of encounter, which setting device has two actuators mounted pivotably at the rear Journalling means of the lifting arms and at the stand parts, whereby the headbox is adjustable by means of a turning movement about said front bearing means of the lifting arms.