Mic Archive
AEA KU4
Photo: Audio Engineering Associates, from its spec sheet, p. 1.

Audio Engineering Associates

AEA KU4

Passive ribbon, supercardioid (unidirectional), after the RCA KU-3A

Type
Ribbon
Pattern
Supercardioid
Sensitivity
−52 dBV/Pa
Max SPL
140 dB SPL
Impedance
300 Ω
Rated range
30 – 20k Hz

Frequency response

Angle
Distance

Frequency response: from the manual, p. 11. "Data below 200 Hz omitted due to measuring room restrictions"; "Normalized to 0 dB at 1kHz. 1/3 octave smoothing"; 0 dB = 2.5 mV/Pa (-52 dBV). A gated CLIO measurement ("Start 2.70ms Stop 9.49ms"); distance 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 (Recording Hacks copy), p. 2. "AEA KU4 Polar Response"; rings every 3 dB, labelled 0 to -30 dB. Measuring conditions not stated.

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All specs

From the manual
Capsulepure aluminium corrugated ribbon, 1.8 µm thick, 2.1 mm wide, 28.6 mm long; neodymium magnets, custom AEA transformer. Magnets and transformer from the one-sheet, p. 1; the ribbon is "Authentic New Old Stock RCA ribbon material" there.p. 10
Sensitivity−52 dBV/Pa (2.5 mV/Pa), 1 kHz, into an unloaded circuit; also −51.1 dBV/Pa, 2.8 mV/Pa, 2010 one-sheet (converted). "-52dBV (2.5 mV/Pa) (at 1 kHz into unloaded circuit)". The 2010 one-sheet says "2.8 mV/Pa into unloaded circuit".
Max SPL140 dB SPL, above 200 Hz, 1% third harmonic. "140+ dB SPL above 200 Hz for 1% third harmonic"; the one-sheet agrees.
Output impedance300 ohm, nominal
Rated load impedance1500 ohm, or greater; also 1200 ohm, 2010 one-sheet. The one-sheet says "1.2 KΩ or greater".
Rated frequency range30 Hz to 20 kHz, "<30 Hz to >20 kHz". Manual p. 4: response "out to 20 kHz (-7 dB)". The one-sheet: "Below 30 Hz to above 20 kHz", and "out to 40 kHz" on p. 1.
Poweringnone (phantom not required or recommended). Manual p. 5: phantom is little danger with a correct cable, but a miswired one can stretch or break the ribbon.
ConnectorXLR-3M on a 1.5 m captive cable (pin 2 high for positive pressure on the front)
Weight2150 g, with its captive cable. "4.7 lb (2.15 kg)"; the one-sheet says "weight with cable".
Dimensions320 × 117 × 94 mm. "Height: 12.6 in (32.00 cm), Width: 4.6 in (11.68 cm), Depth: 3.7 in (9.40 cm)". The one-sheet: 12.65" (32.4 cm), 4.62" (11.7 cm), 3.75" (9.5 cm).
Supplied accessoriesstorage case; stand adapter; user manual. The one-sheet: "Custom storage/shipping case, stand adapter, manual".
Relative output at 180°-12 dB
Angle of maximum rejection135° (± 135° from the front axis)
Shipping weight7.0 lb (3.20 kg)
Shock mountIntegrated cushion mount in a yoke; rotate the mic in the yoke rather than on the standp. 7
Proximity effectReduced; designed for close placementp. 4
WarrantyOne year parts and labour; three years when the product is registered
From the spec sheet (Recording Hacks copy)
FinishAnodised and nickel-plated. "High-quality anodized & nickel-plated finish".p. 1
Ribbon assemblyField-tech replaceable pole piece and ribbon assembly
OptionsM (hand tuning to stereo match a pair)p. 2
Optional accessoriesB gray twill zippered bag; AD-1 5/8"-27 F to 1/2-NPS M stand adapter; 44VC and 44VC-2 vertical carry cases

Documents

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

Product page on aearibbonmics.comRecording Hacks

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