If the receiver antenna connectors are on its rear panel and the rack or case is metal or has a metal frame, the radio signal will be at least partially blocked and performance will almost certainly suffer greatly. Even if the antenna connectors are on the receiver front panel, they will be close to the metal structure and each other, resulting in at least some loss in performance. This arrangement also results in poor reception when the metal rack or case is between the transmitters and the receiving antennas.
The best solution to this problem is to use remote antennas; that is, antennas other than the whip antennas attached directly to the connectors on the receiver. This can be as simple as remounting the whip antennas on the top of the metal cabinet or using accessory antennas. It may also be desirable to have the antennas at some distance from the receivers. This allows the receivers to be positioned conveniently next to the mixer while keeping the antennas in a favorable location nearer the transmitters.
There is more to remote antennas than may meet the eye. If you’re considering going this route, we recommend that you call Sweetwater for more information regarding your system.