The Sennheiser EW-D SK (R4-9) is a digital wireless bodypack transmitter from the flagship EW-DX series, operating in the R4-9 frequency band (552 to 607 MHz). This compact and rugged transmitter is designed to be worn by a performer, converting an analog audio signal from a connected lavalier, headset, or instrument into a secure, high-fidelity digital wireless transmission. It features a robust metal casing, a clear OLED display for monitoring settings and battery status, and a locking connector for secure attachment of microphone cables. The transmitter is powered by two standard AA batteries, offering extended operational time for long performances or shoots.

Utilizing the advanced technology of the EW-DX platform, the SK transmitter delivers 24-bit/48 kHz digital audio quality, ultra-low latency, and 128-bit AES encryption for secure communications. It is designed to pair seamlessly with EW-D series receivers. Whether used by a news presenter with a lavalier, a vocalist with a headset, or a guitarist with a direct input, the EW-D SK bodypack provides reliable, cable-free mobility without compromising on the audio quality demanded by professional broadcast, theater, and live sound environments.