Neumann U 87AI Multi-pattern mic with K 67 capsule

Neumann U 87AI Multi-pattern mic with K 67 capsule, omni, cardioid and figure 8 patterns, pad and filter in woodbox (NICKEL) / U 87AI-MT Multi-pattern mic with K 67 capsule, omni, cardioid and figure 8 patterns, pad and filter in woodbox (MATT BLACK)

The Neumann U 87AI comes in Nickel color, and at the same time the Neumann U 87AI-MT comes in Matt Black color. It is a large dual-diaphragm condenser microphone. It is built featuring three directional patterns, that includes figure-8, omnidirectional and cardioid. Theses are selectable with a switch placed below the head grille and the window above this switch is showing the symbol of the selected characteristic. A 10 dB attenuation switch is placed and can be found on the rear. It is designed enabling the microphone for handling the sound pressure levels up to 127 dB without distortion. The low frequency response is capable to be reduced for compensating the proximity effect.

The U 87 Ai is designed to be 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 created flat for frontal sound incidence, even in the upper frequency range. The microphone is capable to be used very close to a sound source having the sound not becoming unnaturally harsh. By means of a high-pass filter, interference through subsonic and low frequencies are reduced.

The circuitry is designed increasing the operational headroom of the U 87 Ai by supplying the bias voltages for the capsule through a reduced resistance. Resulting in a higher sensitivity of 10 dB for identical sound pressure levels, and an improved S/N ratio of 3 dB.

A switch is placed and can be found at the rear which is attenuating the sensitivity by 10 dB. When this switch is activated, the microphone is designed accepting sound pressure levels up to 127 dB (equivalent to a sound pressure of 45 Pa) without distortion.

An additional switch at the rear is allowing to change the microphone's cutoff frequency. This is reducing the low frequency interference directly at the input of the microphone amplifier. This setting also is compensating for the unavoidable bass boost that is occuring 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.