Abstract: The invention presents a subwoofer-loudspeaker box which is essentially built in one piece. This one-piece housing is completed with a separation wall (20) which can be inserted through an installation opening (12). An insertion frame (16) is installed on the inside wall (15) of the box housing (10) to establish the necessary seal between the volumes (28.1, 28.2) which are divided by the separation wall (20). A seal (29) is also provided for the peripheral edge (27) of the separation wall (20). The separation wall (20) is furthermore equipped with a cover plate (21) which closes the installation opening (12) as soon as the separation wall (20) reaches its final position in the box housing (10).