Abstract: For years efforts have been made to construct acoustically completely dead loudspeaker cabinets. Interest has of course been taken in a neutral reproduction of the signals transmitted to the loudspeaker system, without the acoustic image being changed by cabinet resonances or other irrelevant sources of noise. According to the invention one or several of the cabinet walls are constituted by a hollow body (2), into the interior of which a foamed plastic material mixed with grains of comparatively high specific gravity is injected. These grains are sound and vibration absorbing, so that the walls are practically without resonances, and the weight is simultaneously reduced.

Abstract: In a bass-reflex enclosure or cabinet of the kind in which a loudspeaker unit is mounted in an opening (11) of a front plate (10) and at the end of two coaxially mounted and into the interior of the cabinet extending tubular members (13, 14), so that an annular slot (28) around the speaker unit (16) is provided and in a known manner utilized as a bass-reflex port arranged coaxially with the speaker unit (16), said speaker unit is fixedly mounted on the one end of the inner tube (14) whereas the other outer tube (13) is fixedly mounted to the front plate (10) or forms an integral part therewith. The assembly comprising the inner tube (13) having the speaker unit (16) mounted thereto is suspended to the front plate (10) by means of a number of vibration absorbing rubber blocks (22) which are evenly distributed along the periphery of the speaker. Thereby an acoustically dead front plate (10) is achieved.