Abstract: According to the state of the art, double chamber bass reflex boxes are constructed so that the housing is separated by a partition wall into two spaces (13, 14). A loudspeaker (19) is inserted into the partition wall. One of the two spaces (13, 14) is equipped with an outlet opening, into which a so-called bass reflex tube is inserted for tuning the box. If complicated housing shapes are to be manufactured, it is not possible to build the bass reflex tube and the wall to which it is connected, in one piece. In such instances it is rather necessary to insert the so-called bass reflex tube into an opening in the wall, and to attach it by means of suitable sealing and connecting means. For that reason the invention has the task of presenting a housing for double chamber bass reflex boxes (10) which is especially easy to produce.

Abstract: It is known in the state of the art to equip conical loudspeakers, which are suitable for reproducing long excursion or wide band audio signals, with magnet systems (10), which contain a ring-shaped permanent magnet (12) made of ferrite. To make the induction, required by these magnet systems (10), available in the air gap (20), it is necessary to design the permanent magnets (12) in a large size. It is also known to construct short excursion magnet systems in such a way, that the pole core is made of a high energy magnetic material (-neodymium). This pole core is located in the center of a pot magnet. Such magnet systems, which have the same output and can be built considerably smaller and lighter than the types of magnet systems (10) mentioned first, cannot be transferred to the magnet systems (10) that are suitable for the reproduction of wide band or long excursion audio signals, because a neodymium pole core is not able to produce the induction in the air gap required by such magnet systems (10).

Abstract: A sub-woofer arrangement for the reproduction of bass tones is provided in an armrest of a seat of a passenger car. The sub-woofer arrangement has a sound outlet orifice positioned so as to face a dashboard when lowered in a first position and be unobstructed when raised into a second position in a recess within the seat.

Abstract: A secure joint between heavy magnet systems (11) and plastic loudspeaker frames (12) in conical loudspeakers (10) is conventionally implemented as an adhesive joint or as a shaved rivet joint. These types of joint are disadvantageous, since solvents are necessary when the components are adhesively bonded, and expensive plastics must be used for the shaved rivet joint. Residue-free separation of components joined in this manner is also difficult. Joints that create a secure joint on the basis of mechanically acting components alone are therefore indicated. According to one embodiment of the invention, the magnet system (11) is set into a plastic shroud (31) that has a convex base (32) and a crenelated rim region (36). The higher rim segments (37.2) are guided through openings (38) in the frame base (18) and expanded like rivet heads above the frame base (18), while the other rim segments (37.1) rest on the frame base (18).