The Sennheiser AB 4-AW+ is an advanced, active inline antenna booster engineered to significantly enhance the performance and reliability of Sennheiser wireless microphone and in-ear monitor systems operating in the A-band frequency range (516-558 MHz). This updated "+" model represents an evolution in antenna boosting technology, designed to overcome signal degradation caused by long coaxial cable runs, RF splitters, and challenging venue geometries that can weaken the RF signal before it reaches the receiver. By inserting this compact, low-noise amplifier directly into the antenna signal path, it provides substantial clean gain, effectively extending the operational range of the wireless system and improving reception sensitivity, which is critical for preventing dropouts in mission-critical live, broadcast, and installed sound applications.

The AB 4-AW+ distinguishes itself through its improved circuitry and operational features. It boasts an exceptionally low noise figure, ensuring the amplified signal retains its integrity without introducing significant noise or intermodulation distortion that could interfere with other wireless channels. A key convenience is its dual powering capability; it can be powered either via standard 12V DC phantom power supplied directly from compatible Sennheiser receivers over the coaxial cable or through an optional external power supply (PS 4), offering flexibility in various installation scenarios. This ensures reliable operation even when used with receivers or distribution systems that may not provide sufficient phantom power. A clear LED indicator provides immediate visual feedback on the operational status and power source.

Housed in a robust, die-cast zinc alloy casing, the booster is built for durability in both touring racks and permanent installations. Its simple, two-port design (BNC input and output) makes integration straightforward. For audio engineers and system technicians, the Sennheiser AB 4-AW+ is an indispensable tool for optimizing wireless system robustness. It is particularly effective when used in conjunction with remote directional antennas, allowing the full benefit of optimized antenna placement to be realized at the receiver location, thereby ensuring maximum RF signal strength, stability, and clear audio transmission for performers and presenters.