Williams Sound IR Body Pack 4 Ch Recv Only 2.3/2.8/3.3/3.8 M

The Williams Sound WIR RX22-4N is a four-channel selectable infrared receiver compatible with transmitters operating at 2.3, 2.8, 3.3, and 3.8 MHz. Its body-pack design combines a dual-lens detector with a 3 ft lanyard, allowing the receiver to be worn around the neck. A four-position rotary channel selector, combined power and volume thumbwheel, and 3.5 mm audio output provide direct control over channel selection and listening level.

Ideal Use Cases

The WIR RX22-4N is designed for infrared audio systems that use compatible transmitters across its four supported carrier frequencies. Selectable channels make one receiver suitable for systems transmitting different audio programs at 2.3, 2.8, 3.3, or 3.8 MHz. Its body-pack format and neck lanyard support personal listening without requiring the receiver to remain in a fixed position. The 3.5 mm jack accommodates compatible mono or stereo headphones and earphones rated from 8 to 32 ohms.

Why Choose This Model

This receiver combines four-channel selection with a compact enclosure measuring 4.1 inches long, 2.85 inches wide, and 1.2 inches high. It weighs 4.5 oz with batteries and has a black finish. The dual-lens detector is integrated into the body-pack receiver, while the supplied receiver style includes a 3 ft lanyard for neck-worn operation. A red LED confirms that the receiver is on and flashes when the battery is low, giving the user a clear indication of operating and battery status.

Power can be supplied by two AA alkaline batteries or two AA NiMH batteries. Alkaline batteries provide 60 hours of stated battery life, while NiMH batteries provide 30 hours per charge. The receiver also has charging contacts intended exclusively for use with the CHG 3512 charger.

Installation and Integration

Integration centers on matching the receiver channel to a compatible infrared transmitter. Channel 1 operates at 2.3 MHz, Channel 2 at 2.8 MHz, Channel 3 at 3.3 MHz, and Channel 4 at 3.8 MHz. The four-position rotary switch provides channel selection, and the combination thumbwheel controls power and listening volume. After connecting a compatible listening device to the 3.5 mm stereo mini phone jack, the receiver can accept either a mono or stereo 3.5 mm phone plug.

Compatible Williams Sound listening devices listed for the receiver include the HED 021, HED 026, EAR 013, EAR 014, EAR 022, and NKL 001. The supported operating temperature range is 10°C to +50°C. Systems using rechargeable NiMH batteries can integrate the receiver with the CHG 3512 through its dedicated charging contacts.

Performance Highlights

• Four selectable infrared carrier frequencies: 2.3, 2.8, 3.3, and 3.8 MHz.
• Electrical frequency response of 25 Hz to 16 kHz, rated at +1 dB and -3 dB.
• Minimum signal-to-noise ratio of 60 dB.
• Receiver squelch mutes the output at a 28 dB signal-to-noise ratio.
• Total harmonic distortion is less than 1 percent for the electrical response.
• Sensitivity is better than 1 nW/cm² for a 40 dB signal-to-noise ratio.
• Maximum audio output power is 15 mW at 32 ohms.
• FM deviation is ±50 kHz, with 50 uS de-emphasis.

Acoustic output depends on the connected listening device. The specified output is 125 dB SSPL90 with the HED 021 and 110 dB SSPL90 with the EAR 013. Nominal battery drain is 25 mA.

What Makes It Different

The defining feature of the WIR RX22-4N is the combination of four selectable infrared channels in a wearable receiver. Users can move among the four supported frequencies with a dedicated rotary selector while retaining a single power and volume control. The dual-lens body-pack construction, neck lanyard, low-battery indication, and compatibility with both alkaline and rechargeable NiMH AA batteries support flexible day-to-day operation. CE, FCC, RoHS, and WEEE approvals are listed for the receiver.

Final Assessment

The WIR RX22-4N is a focused four-channel receiver for compatible Williams Sound infrared systems. It provides selectable 2.3, 2.8, 3.3, and 3.8 MHz operation, broad compatibility with 3.5 mm mono and stereo listening devices, and defined audio performance in a wearable body-pack format. The receiver carries a five-year warranty, while accessories carry a 90-day warranty.