The Neumann U 87 Ai is a large-diaphragm condenser microphone with a dual-diaphragm capsule. A switch below the headgrille selects one of three polar patterns: omnidirectional, cardioid or figure-8. A window above the switch shows the selected pattern. The microphone is addressed from the front, marked with the Neumann logo.
It is used as a vocal microphone for music and speech, as a main microphone for orchestra recordings, and as a spot mic for single instruments. It is used in studios, broadcasting, film and television. This offering is a factory-matched stereo pair of two U 87 Ai microphones with EA 87 suspension mounts in a mic briefcase, in a black finish.
The Ai version keeps the original capsule and has updated electronics. The circuitry supplies the capsule bias voltages through a reduced resistance. This gives 10 dB higher sensitivity for the same sound pressure level and a 3 dB better signal-to-noise ratio. A second rear switch lowers the low-frequency response to reduce hum, rumble and proximity effect. The cardioid pattern keeps a smooth response at 30 to 40 cm, and the figure-8 pattern at 15 to 20 cm.
- Transducer
- Pressure gradient condenser
- Polar patterns
- Cardioid, omnidirectional, figure-8
- Frequency response
- 20 Hz - 20 kHz
- Dynamic range
- 115 dB (A-weighted), typical
- Signal-to-noise
- 82 dB cardioid, 79 dB omnidirectional, 80 dB figure-8 (A-weighted)
- Max input level
- 117 dB at 1 kHz, 0.5% THD; 127 dB with pad
- Pad
- -10 dB preattenuation
- Low cut
- Switchable low-frequency roll-off
- Power
- Phantom 48 V (±4 V)
- Output impedance