Omnidirectional Condenser Boundary Microphone

$375 + shipping (includes gst)

The U841A delivers exceptionally intelligible audio reproduction in a super-compact, low-profile design. Equipped with UniGuard® RFI-shielding technology, this omnidirectional condenser boundary microphone is designed for clear, highly intelligible sound reinforcement, professional recording, television and conferencing in surface-mount applications. The U841A has a 360° pickup angle and operates on battery or phantom power.

  • Designed for surface-mount applications such as high-quality sound reinforcement, professional recording, television, conferencing and other demanding sound pickup situations
  • UniGuard® RFI-shielding technology offers outstanding rejection of radio frequency interference (RFI)
  • UniSteep® filter provides a steep low-frequency attenuation to improve sound pickup without affecting voice quality
  • Small-diameter UniPoint® capsule near boundary eliminates phase distortion and delivers clear, high-output performance
  • Heavy die-cast case and silicon foam bottom pad minimize coupling of surface vibration to the microphone
  • Low-profile design with low-reflectance black finish for minimum visibility
  • Operates on battery or phantom power

Fixed-charge back plate permanently polarized condenser

Polar Pattern

Omnidirectional in hemisphere above mounting surface

Frequency Response

30-20,000 Hz

Low Frequency Roll-Off

80 Hz, 18 dB/octave

Open Circuit Sensitivity

Phantom: –39 dB (11.2 mV) re 1V at 1 Pa 
Battery: –40 dB (10.0 mV) re 1V at 1 Pa


Phantom: 200 ohms 
Battery: 270 ohms

Maximum Input Sound Level

Phantom: 132 dB, 1 kHz at 1% T.H.D. 
Battery: 122 dB SPL, 1 kHz at 1% T.H.D. 

Dynamic Range (Typical)

Phantom: 111 dB, 1 kHz at Max SPL 
Battery: 101 dB, 1 kHz at Max SPL

Signal-To-Noise Ratio

73 dB, 1 kHz at 1 Pa

Phantom Power Requirements

11-52V DC, 2 mA typical

Battery Type

1.5V AA/UM3

Battery Current / Life

0.4 mA / 1200 hours typical (alkaline)


Off, on-flat, on-roll-off

Weight (Microphone)

2.8 oz (78 g)

Weight (Power Module)

4.9 oz (139 g)

Dimensions (Microphone)

2.56″ (65.0 mm) diameter, 
0.59″ (15.1 mm) height

Dimensions (Power Module)

3.31″ (84.0 mm) H x 
2.48″ (63.0 mm) W x 
0.87″ (22.0 mm) D

Output Connector (Power Module)

Integral 3-pin XLRM-type


25.0′ (7.6 m) long (permanently attached to microphone), 0.13″ (3.2 mm) diameter, 2-conductor, shielded cable with TA3F-type connector

Accessories Furnished

AT8531 power module; battery

Polar Pattern
Frequency Response
U841a Spec Sheet (PDF) Download
U841a Submittal Sheet (PDF) Download

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