Audio-Technica AT831CW Cardioid Lavalier Microphone

Audio-Technica AT831cW Cardioid Lavalier Microphone

The Audio-Technica AT831cW is a miniature cardioid condenser lavalier microphone made for wireless work. It clips to clothing, picks up the voice clearly from a short distance and connects to a compatible Audio-Technica UniPak bodypack transmitter through a locking four-pin connector. Because this version is supplied without a power module, it draws its operating power from the bodypack itself, which keeps the part worn on the body as small and light as possible.

The microphone itself weighs just 2.8 grams and measures 25 mm long with a 10.2 mm diameter, so it sits discreetly on a lapel, tie or collar without pulling the fabric out of shape. Its cardioid polar pattern concentrates on sound arriving from the front of the capsule, which helps reject room noise and reduces the risk of feedback when the wearer is working near loudspeakers.

Key features

• Miniature cardioid condenser capsule tuned for crisp, full-sounding voice pickup
• Locking four-pin connector made for Audio-Technica UniPak bodypack transmitters
• 1.4 m cable permanently attached to the microphone, so there is no loose connector at the capsule end
• Very light 2.8 g microphone body that clips on without dragging on clothing
• Frequency response of 40 Hz to 16,000 Hz, covering the full range of speech
• Clothing clip and windscreen included for immediate clip-on use

Sound and pickup pattern

A lavalier lives or dies by placement, and the cardioid pattern of the AT831cW gives the wearer a useful margin. Positioned on the chest, roughly a hand’s width below the chin, it captures the voice with good presence while picking up less of the room than an omnidirectional capsule would. That directionality is valuable in reverberant halls, classrooms and places of worship, where reflected sound can blur speech. It also improves gain before feedback in live reinforcement, letting the presenter move more freely in front of the speakers.

Built for wireless systems

The cW suffix matters. Other versions of the AT831 are terminated differently, including wired models that use a separate power module and a standard XLR output. The AT831cW instead ends in a locking four-pin plug wired for UniPak bodypacks, and the locking collar keeps the connection secure when the wearer moves, turns or gestures. A transmitter and receiver are still required to complete the system; this microphone is the capsule and cable portion of that chain.

Placement and everyday use

Clip the microphone clear of necklaces, buttons and fabric edges that could rub against the capsule, and loop a small amount of cable slack near the clip so movement does not tug on it. The supplied windscreen softens breath pops and light air movement. The same capsule also works as an instrument microphone for acoustic guitar when used with the appropriate adapter, which makes it a flexible addition to a wireless kit rather than a single-purpose speech mic.

For presenters, teachers, interviewers, performers and speakers who already run UniPak bodypacks, the AT831cW offers a proven, discreet way to get consistent voice pickup without holding a microphone or standing at a lectern.