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AKG C 391 B
Photo: AKG (Harman), from its manual, p. 1.

AKG Acoustics

AKG C 391 B

Small-diaphragm condenser, cardioid: the SE 300 B powering/output module with the screw-on CK 91 capsule (Blue Line modular system)

Type
Condenser (electret)
Pattern
Cardioid
Sensitivity
−40 dBV/Pa
Self-noise
17 dB(A)
Max SPL
132 dB SPL
Impedance
200 Ω
Rated range
20 – 20k Hz

Frequency response

Angle
Distance

Frequency response: from the manual, p. 21. "Frequency Response Curve"; relative dB. Distance, field 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 manual, p. 21. "Polar Pattern"; 125 Hz to 1 kHz on the left half, 2 to 16 kHz on the right; 0° at the bottom, rings every 5 dB, centre -25 dB.

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All specs

From the manual
CapsuleCK 91 cardioid capsule on the SE 300 B module (bayonet mount, interchangeable)p. 14
Sensitivity−40 dBV/Pa (10 mV/Pa), at 100 Hz (as printed). "Field open loop gain (sensitivity) at 100 Hz: 10 mV/Pa - 40 dBV"; every language says 100 Hz, where 1 kHz is usual.p. 20
Self-noise17 dB(A), IEC 60268-4, A-weighted
Max SPL132 dB SPL, 1000 Hz. "Sound pressure limit: 80 Pa (132 dB) for 1000 Hz"; no distortion figure given.
Signal-to-noise ratio77 dB, re 1 Pa, A-weighted
Output impedance200 ohm
Rated load impedance1000 ohm, recommended
Rated frequency range20 Hz to 20 kHz, ± 2 dB from the nominal curve
Poweringphantom, 9 to 52 V (IEC 61938)
Current draw2 mA. "Current consumption: 2 mA" (the sign before 2 is lost in the PDF text; probably "<").
Low cutoff, 75 Hz; 75 Hz; 12 dB/octave. "The filter slope is approx. 12 dB/octave with the corner frequency (-3 dB point) lying at approx. 75 Hz"; p. 14 says the onset is at about 100 Hz.p. 16
Pad−10 dB. "Integrated, switchable 10 dB attenuation of gain".p. 14
ConnectorXLR-3 male. "Type XLR-3 acc. to IEC".p. 20
Weight115 g, net, approx.
Dimensions19 × 147 mm. Diameter × length.
Finishmat grey (brass housing)
Supplied accessoriesW 90 foam wind guard; SA 60 universal stand connector. Scope of supply.p. 14
Acoustic working principlePressure gradient receiverp. 20
Operating conditions-20 °C to +60 °C; relative humidity 99% (+20 °C), 95% (+60 °C)
Output stageTransformerlessp. 14
Other capsules for the SE 300 BCK 92 omni, CK 93 hypercardioid, CK 94 figure-eight, CK 97C miniature cardioid, CK 98 short shotgunp. 17
Optional accessoriesA 91 articulated joint (±90°), B 18 battery supply, H 30 elastic suspension, ST 45 / ST 46 / ST 305 table standsp. 15

Documents

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

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