Antenna systems, such as an active antenna system (AAS), can include active and passive electronic components located closely together inside an antenna system. Such systems may benefit from variable adaptation of active antenna system radio frequency signal filtering. An apparatus can include an active part on a first end of a signal path within a sealed enclosure. The apparatus can also include a radiator part on a second end of the signal path within the sealed enclosure. The apparatus can further include an intermediate part, which includes at least one of an additional filter part or a customized passive part, positioned between the active part and the radiator part along the signal path between the first signal side and the second signal side.