Mic Archive
Audio-Technica AT831b
Photo: Audio-Technica, from its spec sheet, p. 1.

Audio-Technica

Audio-Technica AT831b

Miniature condenser (fixed-charge back plate), cardioid, clip-on lavalier and instrument mic, with a power module for phantom or AA battery and an 80 Hz UniSteep high-pass

Type
Condenser (electret)
Pattern
Cardioid
Sensitivity
−44 dBV/Pa
Self-noise
29 dB(A) computed
Max SPL
135 dB SPL
Impedance
200 Ω
Rated range
40 – 18k Hz

Frequency response

Angle
Distance

Frequency response: from the spec sheet, p. 1. Printed under the graph: "12\" or more on axis" (30 cm or more). Room and smoothing not stated.

Dashed: outside the rated range, or simulated (other angles and distances). Hover or tap the graphs for values.

Polar pattern

Polar pattern: from the spec sheet, p. 1. Full circle, 0° at the top, "SCALE IS 5 DECIBELS PER DIVISION". Measuring conditions not stated.

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All specs

From the spec sheet
Sensitivity−44 dBV/Pa (6.3 mV/Pa), open circuit, phantom power; also −46 dBV/Pa, open circuit, battery. "–44 dB (6.3 mV) / –46 dB (5.0 mV) re 1V at 1 Pa" (Phantom / Battery).p. 1
Self-noise29 dB(A), typical, A-weighted. Not stated; computed as 94 dB SPL minus the signal-to-noise ratio, "65 dB, 1 kHz at 1 Pa" (typical, A-weighted).
Max SPL135 dB SPL, 1 kHz, 1% THD, phantom power; also 121 dB SPL, 1 kHz, 1% THD, battery. "135 dB / 121 dB SPL" (Phantom / Battery).
Signal-to-noise ratio65 dB, 1 kHz at 1 Pa; typical, A-weighted
Dynamic range106 dB, 1 kHz at max SPL, typical, phantom power; also 92 dB, battery. "106 dB / 92 dB" (Phantom / Battery).
Output impedance200 ohm, phantom power; also 270 ohm, battery. "200 ohms / 270 ohms" (Phantom / Battery); low impedance balanced.
Rated frequency range40 Hz to 18 kHz. Tolerance not stated.
Poweringphantom 11-52 V DC, or one 1.5 V AA battery, in the AT8531 power module. "The AT831b requires 11-52V DC phantom power, or a 1.5V AA battery for operation. A battery need not be in place for phantom power operation."
Current draw2 mA, phantom, typical; also 0.4 mA, battery. Phantom "11-52V DC, 2 mA typical"; battery "0.4 mA / 1200 hours typical (alkaline)".
Low cutflat, roll-off; 80 Hz; 18 dB/octave; high-pass. "80 Hz, 18 dB/octave"; switch "Off, on-flat, on-roll-off"; an "integral 80 Hz high-pass UniSteep® filter".
ConnectorTA3F on the fixed 1.8 m cable, into the power module; XLR-3 male on the power module. Output connector "Integral 3-pin XLRM-type (power module)"; cable "with TA3F-type connector".
Weight2.8 g, microphone, less cable and accessories; power module 139 g
Dimensions10.2 × 25 mm. Microphone diameter × length: "25.0 mm (0.98") long, 10.2 mm (0.40") diameter".
Supplied accessoriesAT8531 power module; AT8419 clothing clip; AT8444 instrument adapter; AT8116 windscreen; battery; protective carrying case
SwitchOff, on-flat, on-roll-off (on the power module)
Battery1.5 V AA/UM3; 0.4 mA, about 1200 hours (alkaline, typical)
Power module size84.0 × 63.0 × 22.0 mm (H × W × D)
Cable1.8 m, permanently attached to the mic, 2.6 mm diameter, 2-conductor shielded, TA3F-type connector
Placement (Audio-Technica)As a lavalier, about six inches (15 cm) below the chin; also for acoustic guitar with the AT8444 instrument adapter
OutputLow impedance balanced, pin 2 hot
Operating temperatureAvoid more than 43 °C (110 °F) for long periods, and very high humidity

Documents

Copies kept by Mic Archive, because manufacturers move and drop their documents. Each is © Audio-Technica, unchanged, with its original address.

Product page on audio-technica.comRecording Hacks

Recommended for

Instruments whose sources name this mic, or an earlier version or variant of it.

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