The Sennheiser EM 300 is a professional true diversity UHF wireless receiver designed for reliable audio transmission in live sound, broadcast, and theatrical applications. Operating within a selectable frequency range, this receiver employs a true diversity system with two separate antenna inputs and independent RF circuits. It continuously monitors the signal strength on both antennas and instantaneously switches to the antenna providing the stronger, clearer signal, effectively combating dropouts and interference caused by multipath reflections or obstructions. This results in a stable, robust wireless link for microphones or instruments, which is critical in environments where a cable-free performance is essential.

The receiver is engineered for ease of use and integration. It features a clear front-panel display that shows frequency, battery status of the connected transmitter, audio level, and RF signal strength. Users can select from a wide range of pre-programmed frequency banks and channels to find an interference-free frequency, and the unit supports multiple systems operating simultaneously within the same location. Audio output is provided via balanced XLR and unbalanced 1/4-inch jacks, and the receiver includes features like adjustable squelch to minimize noise when no signal is present, and adjustable audio gain. It is typically rack-mounted in a 1U or 2U chassis, making it a standard component in professional audio racks for touring or installed systems.

Powered by an external AC adapter, the EM 300 is built to Sennheiser's renowned standards for audio quality and reliability. It is often paired with compatible Sennheiser bodypack or handheld transmitters (like the SK series) and microphones. By providing a secure, high-fidelity wireless connection, the Sennheiser EM 300 receiver empowers performers and presenters with freedom of movement while delivering the audio clarity and consistency demanded by professional users.