A battery powered wireless audio speaker comprising a passive radiator is disclosed. The perimeter portion of the passive radiator is sandwiched between the speaker chassis and the retention gasket that resides between an external overlying perforated cover to firmly secure the passive radiator. The construction is capable of being well suited to enhance and improve integrity to the seal between the passive radiator and the speaker chassis in strenuous environment conditions such as when a speaker is submerged in water.