Neumann U 87 Ai User Manual

Product Information

U87Ai

Large Diaphragm
Microphone

www.neumann.com

Georg Neumann GmbH • Ollenhauerstr. 98 • 13403 Berlin • Germany • Tel.: [phone] • Fax: [phone]
E-Mail: [e-mail], [e-mail], [e-mail] • Web: www.neumann.com

he U 87 is probably the best known
and most widely used Neumann studio micro­phone. It is equipped with a
large dual-diaphragm capsule
with three directional pat­terns: omnidirectional, car­dioid and figure-8. These are
selectable with a switch below
the headgrille.

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.

Furthermore, the low fre­quency response can be reduced to compen­sate for proximity effect.

Applications

The U 87 Ai condenser microphone is a large
diaphragm microphone with three polar pat­terns and a unique frequency and transient re­sponse characteristic.

Users recognize the microphone immediately
by its distinctive design. It is a good choice for
most general purpose applications in studios,
for broadcasting, film and television.

The U 87 Ai is used as a main microphone for
orchestra recordings, as a spot mic for single
instruments, and extensively as a vocal micro­phone for all types of music and speech.

Acoustic features

The U 87 Ai is addressed from the front, mark­ed with the Neumann logo.

The design of the microphone is a registered design of the Georg Neumann GmbH in certain countries.

Features

• Variable large diaphragm
microphone

• Pressure-gradient transducer
with double membrane capsule

• The studio microphone classic

• Three directional characteri­stics: omni, cardioid, figure-8

• Switchable low frequency
roll-off

• Switchable 10 dB pre­attenuation

• Ideal as main and as support
microphone in the most
differing recording situations

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
interferences through subsonic
and low frequencies are reduced remarkably.

Polar patterns

The dual-diaphragm capsule is elastically
mounted and protected by a
large headgrille.

A switch below the headgrille
selects the three directional
patterns: omnidirectional, car­dioid and figure-8.

A window above this switch
shows the symbol of the se­lected characteristic.

Electrical features

U87Ai

Application Hints

• For universal use

• The classical studio mic for vocalists (soloists and
background vocalists)

• Announcer’s mic for broadcasting, dubbing,
voice-over

• Overhead

• Spot mic for

- wind instruments

- strings (especially cello and double bass)

- piano

- percussion

• Note: To record instruments with very high sound
pressure levels we recommend our mics with
TLM circuitry

The letter A in the name indicates a more re­cent generation, as compared to the U 87 i mi­crophones that were built from 1967 to 1986.
Modifications apply to the electronic compo­nents of the microphone only; the capsule re­mained unchanged.

The present-day circuitry increases the 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.

Filter and attenuation

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, the figure-8 characteristic even at a di­stance of 15 to 20 cm.

These are just some of the most common
applications. We recommend additional experimen­tation to gain maximum use from this microphone.

Delivery Range

Microphone U 87 Ai (mt) in Wooden box

Stereo set:Stereo set:

Stereo set: 2x U 87 Ai (mt) Microphone, 2x

Stereo set:Stereo set:
EA 87 (mt) Elastic suspension, 2x Dust cover,
Aluminium case

Catalog No.

U 87 Ai ...........................................................ni .......... 007022

U 87 Ai mt ................................................... blk ....... 007023

U 87 Ai Stereo set .................................. ni .......... 008505

U 87 Ai mt Stereo set .......................... blk ....... 008506

Selection of Accessories

Battery supply, BS 48 i ........................ blk ....... 006494

Power supply, N 248 EU .................. blk ....... 008537

Power supply, N 248 US ................... blk ....... 008538

Power supply, N 248 UK .................. blk ....... 008539

Auditorium hanger, MNV 87 ...........ni .......... 006804

Auditorium hanger, MNV 87 mt ... blk ....... 006806

Elastic suspension, EA 87 ................. ni .......... 007297

Elastic suspension, EA 87 mt ......... blk ....... 007298

Stand mount swivel, SG 367 mt ... blk ....... 006145

Popscreen, PS 20 a ................................ blk ....... 008488

Windscreen, WS 87 ............................... blk ....... 006753

Microphone cable, IC 4 mt ................ blk ....... 006557

A complete survey and detailed descriptions of all
accessories are contained in the accessories
catalog.

Meaning of color codes: blk = black, ni = nickel

measured in free-field conditions (IEC 60268-4), tolerance ±2 dB

Technical Data

Acoustical operating principle ............................ Pressure gradient transducer

Directional pattern ......................................... Omnidirectional, cardioid, figure-8

Frequency range ..................................................................................... 20 Hz...20 kHz

Sensitivity at 1 kHz into 1 kohm ........................................... 20/28/22 mV/Pa

Rated impedance ................................................................................................. 200 ohms

Rated load impedance .................................................................................. 1000 ohms

Signal-to-noise ratio, CCIR2) (rel. 94 dB SPL) ........................... 68/71/69 dB

Signal-to-noise ratio, A-weighted2) (rel. 94 dB SPL) ............. 79/82/80 dB

Equivalent noise level, CCIR2).............................................................. 26/23/25 dB

Equivalent noise level, A-weighted2).......................................... 15/12/14 dB-A

1)

Omnidirectional / cardioid / figure-8 2) according to IEC 60268-1; CCIR-weighting acccording to CCIR 468-3, quasi peak; A-weighting according to IEC 61672-1, RMS 3) measured as equivalent el. input signal

Errors excepted, subject to changes • Printed in Germany • Publ. 09/07 058152/A05

Neumann is a registered trademark of the Georg Neumann GmbH in certain countries.

®

Maximum SPL for THD 0.5%3)................................................ 117 dB (cardioid)

Maximum SPL for THD 0.5% with preattenuation3)........................ 127 dB

Maximum output voltage ................................................................................... 390 mV

1)

Dynamic range of the microphone amplifier, A-weighted ............. 105 dB

Supply voltage (P48, IEC 61938) .......................................................... 48 V ± 4 V

Current consumption (P48, IEC 61938) .................................................... 0.8 mA

1)

Matching connector ................................................................................................... XLR3F

1)

Weight.................................................................................................................................. 500 g

1)

Diameter .......................................................................................................................... 56 mm

1)

Length............................................................................................................................ 200 mm