U 87 AI

Large Dual-Diaphragm Condenser Microphone(Studio Set)

Overview
U 87 Ai Condenser Microphone from Neumann is a large dual-diaphragm condenser microphone. It features three directional patterns, including omnidirectional, cardioid and figure-8. These are selectable with a switch below the head grille and the window above this switch shows the symbol of the selected characteristic. A 10 dB attenuation switch is located on the rear. It enables the microphone to handle sound pressure levels up to 127 dB without distortion. The low frequency response can be reduced to compensate for proximity effect.The U 87 Ai is used as a main microphone for orchestra recordings, as a spot microphone for single instruments, and extensively as a vocal microphone for all types of music and speech.The U 87 Ai is addressed from the front. The frequency response of the cardioid and figure-8 directional characteristics are very flat for frontal sound incidence, even in the upper frequency range. The microphone can be used very close to a sound source without the sound becoming unnaturally harsh. By means of a high-pass filter, interference through subsonic and low frequencies are reduced.The circuitry increases operational headroom of the U 87 Ai by supplying the bias voltages for the capsule through a reduced resistance. The result is a higher sensitivity of 10 dB for identical sound pressure levels, and an improved S/N ratio of 3 dB.

Features

A switch located at the rear attenuates the sensitivity by 10 dB. When this switch is activated, the microphone accepts sound pressure levels up to 127 dB (equivalent to a sound pressure of 45 Pa) without distortion. An additional switch at the rear allows to change the microphone's cutoff frequency. This reduces low frequency interference directly at the input of the microphone amplifier. This setting also compensates for the unavoidable bass boost that occurs with all pressure gradient transducers when they are used at close distance (proximity effect).The cardioid characteristic maintains a smooth frequency response at a distance of 30 to 40 cm, and the figure-8 characteristic at a distance of 15 to 20 cm.

- Variable large diaphragm microphone

- Pressure-gradient transducer with double membrane capsule

- Omnidirectional, cardioid, and figure-8 characteristics

- Switchable low frequency roll-off

- Switchable 10 dB pre-attenuation

- Great as a main or as a support microphone

Specifications          

Analog Performance

Operating Principle        Pressure Gradient

Transducer        Condenser

Polar Pattern     Cardioid, Figure-8, Omnidirectional

Pattern Selection           Switched

Frequency Range          20 Hz to 20 kHz

Signal to Noise Ratio     71 dB CCIR

69 dB CCIR

68 dB CCIR

82 dB A-Weighted

80 dB A-Weighted

79 dB A-Weighted

Equivalent Noise Level  23 dB CCIR

25 dB CCIR

26 dB CCIR

12 dB A-Weighted

14 dB A-Weighted

15 dB A-Weighted

Maximum SPL   117 dB SPL

Pad      -10 dB

THD      0.5%

Impedance        200 Ohms

Load Impedance           1000 Ohms

Sensitivity         28 mV/Pa at 1 kHz into 1 kOhms

22 mV/Pa at 1 kHz into 1 kOhms

20 mV/Pa at 1 kHz into 1 kOhms

General

Output Connectors        1 x 3-Pin XLR

Operating Current Consumption 0.8 µA

Operating Voltage         48V ± 4 V

Length  7.87" / 200 mm

Diameter           2.20" / 56 mm

Weight  1.10 lb / 500 g

Packaging Info

Package Weight            5.65 lb

Box Dimensions (LxWxH)          11.5 x 11.5 x 6.1"

What’s In The Box

- Neumann U 87 Ai Condenser Microphone (Studio Set)

- Neumann EA87 - U87 Shock Mount for U87 Microphones

- Wooden Box