Cardioid Condenser Lavalier Microphone

$369 + shipping (includes gst)

This clip-on lavalier mic provides crisp, full-sounding voice pickup and excels as an instrument mic, especially for pickup of acoustic guitar with included AT8444 guitar adapter. It offers excellent gain before feedback and suppression of background noise. An integral 80 Hz high-pass filter provides easy switching from a flat frequency response to a low-end roll-off. It operates on battery or phantom power.

  • Clip-on lavalier mic also excels in acoustic guitar applications
  • Provides crisp, full-sounding voice and instrument pickup
  • Operates on battery or phantom power
  • 6' (1.8 m) cable permanently attached to mic, TA3F connector at power module

Fixed-charge back plate, permanently polarized condenser

Polar Pattern


Frequency Response

40-18,000 Hz

Low Frequency Roll-Off

80 Hz, 18 dB/octave

Open Circuit Sensitivity

Phantom: -44 dB (6.3 mV) re 1V at 1 Pa 
Battery: -46 dB (5.0 mV) re 1V at 1 Pa


Phantom: 200 ohms 
Battery: 270 ohms

Maximum Input Sound Level

Phantom: 135 dB SPL, 1 kHz at 1% T.H.D. 
Battery: 121 dB SPL, 1 kHz at 1% T.H.D.

Dynamic Range (Typical)

Phantom: 106 dB, 1 kHz at Max SPL 
Battery: 92 dB, 1 kHz at Max SPL

Signal-To-Noise Ratio

65 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)

0.1 oz (2.8 g)

Weight (Power Module)

4.9 oz (139 g)

Dimensions (Microphone)

0.98″ (25.0 mm) long, 
0.40″ (10.2 mm) diameter

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


6′ (1.8 m) long (permanently attached to microphone), 0.10″ (2.6 mm) diameter, 2-conductor, shielded cable with TA3F-type connector

Accessories Furnished

Clothing clip; AT8444 instrument adapter; AT8531 power module; AT8116 windscreen; battery; protective carrying case

Polar Pattern
Frequency Response
AT831B Spec Sheet (PDF) Download
AT831B Submittal Sheet (PDF) Download



Cardioid Condenser Lavalier Microphone

$ 399

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