A passive radiator assembly for a loudspeaker system (1, 10, 100) comprising: a pair of passive radiators including a first and a second passive radiator (50.1, 50.2); and a frame having a first, a second and a third opening (55, 57.1, 57.2) wherein the first and second opening (57.1, 57.2) are located on parallel sides of the frame, respectively, wherein the first and the second passive radiator (50.1, 50.2) are mounted into the first and second opening (57.1, 57.2) of the parallel sides of the frame, respectively, so as to oppose each other at a predetermined distance, wherein the first passive radiator (50.1) has a first maximum excitation amplitude and the second passive radiator (50.2) has a second maximum excitation amplitude, wherein the predetermined distance between the mounted first and second passive radiator (50.1, 50.2) is larger than the sum of the first and the second maximum excitation amplitudes, thereby preventing each passive radiator from touching one another, a total area of the third opening is equal to or larger than 1/8 of a sum of the total area of the first passive radiator (50.1) and the total area of the second passive radiator (50.2) to reduce or avoid air turbulence noise and losses when the passive radiator assembly is mounted in the loudspeaker assembly, wherein the total area of a passive radiator is the surface area of the respective passive radiator, the frame has a fourth side opposite to the third opening, wherein the fourth side together with the first and second passive radiator (50.1, 50.2) mounted into the first and second opening of the parallel sides form three sides of an enclosure, and the fourth side is at least in part semi-circularly shaped to fit to a shape of the first passive radiator and the second passive radiator. a pair of passive radiators including a first and a second passive radiator (50.1, 50.2); and a frame having a first, a second and a third opening (55, 57.1, 57.2) wherein the first and second opening (57.1, 57.2) are located on parallel sides of the frame, respectively, wherein the first and the second passive radiator (50.1, 50.2) are mounted into the first and second opening (57.1, 57.2) of the parallel sides of the frame, respectively, so as to oppose each other at a predetermined distance, wherein the first passive radiator (50.1) has a first maximum excitation amplitude and the second passive radiator (50.2) has a second maximum excitation amplitude, wherein the predetermined distance between the mounted first and second passive radiator (50.1, 50.2) is larger than the sum of the first and the second maximum excitation amplitudes, thereby preventing each passive radiator from touching one another, a total area of the third opening is equal to or larger than 1/8 of a sum of the total area of the first passive radiator (50.1) and the total area of the second passive radiator (50.2) to reduce or avoid air turbulence noise and losses when the passive radiator assembly is mounted in the loudspeaker assembly, wherein the total area of a passive radiator is the surface area of the respective passive radiator, the frame has a fourth side opposite to the third opening, wherein the fourth side together with the first and second passive radiator (50.1, 50.2) mounted into the first and second opening of the parallel sides form three sides of an enclosure, and the fourth side is at least in part semi-circularly shaped to fit to a shape of the first passive radiator and the second passive radiator.