There are known bass reflex boxes which have a bass loudspeaker and a bass reflex opening in an acoustic baffle of a housing with a defined volume. The bass loudspeaker, the bass reflex opening and the volume of the housing are so matched with one another that the impedance curve of the bass reflex box has a maximum at a defined frequency, at which the bass loudspeaker and the air in the bass reflex opening oscillate in phase. To improve the sound radiation, it is proposed to add an open-ended conductor in front of the acoustic baffle that encloses the bass loudspeaker and the reflex opening, and whose length is so determined that the impedance at the defined frequency is reduced.
