Neumann.Berlin M 149 Tube Mode D'emploi page 3

When the directional characteristic is changed,
an increased noise level may occur for a period
of approximately 0 seconds. This does not indi-
cate a malfunction, but arises due to the electri-
cal recharging of the microphone capsule to the
appropriate bias.
Setting the high-pass filter
On the back of the microphone is a slide switch for
a high-pass filter, with seven settings. The cutoff
frequency (− dB) can be selected in half-octave
steps, from 0 Hz to 160 Hz. The high-pass filter
can be used to suppress low-frequency interfer-
ence (e.g. caused by impact sound or wind noise)
or to compensate for the proximity effect.
Suppressing noise interference
The frequency response of the M 149 Tube ex-
tends below 0 Hz. The microphone is of course
correspondingly sensitive to low-frequency inter-
ference such as structure-borne noise and wind
or pop noise. Depending upon the situation, the
use of a windscreen and/or popscreen is therefore
recommended.
7. Troubleshooting
▶
Problem Possible causes
Microphone The power supply unit is not switched on.
not operating
The microphone is not connected to the
power supply unit or is not ready for
operation.
No signal The microphone is not connected to the
transmission correct microphone amplifier input of th
esubsequent equipment.
8. Technical data and
connector assignments
Permissible atmospheric conditions:
1)
Operating temperature range ........... 0 °C ... +70 °C
Storage temperature range ...........−0 °C ... +70 °C
Humidity range ..................... 0 % ... 90 % at +0 °C
0 % ... 8 % at +60 °C
Acoustical op. principle .............Pressure gradient
Directional pattern ........................................ Omni/
wide-angle cardioid/cardioid/
hyper-cardioid/figure-8 and 4 additional
intermediate patterns
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4
Sound test
Simply speak into the microphone. Do not blow
into the microphone or subject it to pop noise,
since this can easily result in hazardous sound
pressure levels.
6. Shutdown and storage
Before switching off the microphone or discon-
necting the cables, reduce the volume of con-
nected equipment.
Only then should the power supply equipment be
switched off.
Disconnect the cables.
When disconnecting a cable, always pull only on
the connector and not on the cable itself.
Microphones which are not in use should not be
allowed to remain on the stand gathering dust.
A microphone which is unused for a prolonged
period should be stored under normal atmo-
spheric conditions, and should be protected from
dust. For this purpose, use a lint-free, air-perme-
able dust cover or the original packaging of the
microphone.
▶
Solution
Check the connection to the power supply
line.
Check the LED status on the power supply
unit.
Check the signal path.
Check the corresponding channel settings.
Frequency range ...............................0 Hz...0 kHz
Sensitivity ................................. 4/47/6 mV/Pa
)
Rated impedance ........................................0 ohms
Rated load impedance ..........................1000 ohms
Signal-to-noise ratio 4) , CCIR ) ......... 66/69/71 dB
Signal-to-noise ratio 4) ,
A-weighted ...................................... 78/81/8 dB
)
Equivalent noise level,
CCIR .................................................8// dB
)
Equivalent noise level,
transducer
A-weighted ) ...................................16/1/11 dB-A
Max. SPL (tube characteristic) 6)
for THD < 0. % ............................................. 10 dB
for THD <  % ................................................. 16 dB
Max. output voltage .......................................18 dBu
Power supply ................................................N 149 A
Required connectors:
Microphone .................................................... DIN8F
Power supply unit ..........................................XLRF
Weight ................................................approx. 70 g
Dimensions ............................... Ø 70 mm x 01 mm
94 dB SPL equiv. to 1 Pa = 10 µbar
0 dB equiv. to 0 µPa
The 8-pin connectors of the microphone and the
power supply unit have the following pin assign-
ments:
Pin 1: −70 V
Pin : + V
Pin : Modulation (+phase)
Pin 4: +70 V
Pin : Sensor line
Pin 6: Ground
Pin 7: + V
Pin 8: Modulation (−phase)
The -pin XLR output of the power supply unit has
the following standard pin assignments:
Pin 1: 0 V/Ground
Pin : Modulation (+phase)
Pin : Modulation (−phase)
Circuit technology information
The operating point of the tube and the heating
voltage are stabilized by a control circuit in the
power supply unit. A sensor circuit detects and
compensates for voltage drops in the microphone
cable for cable lengths of up to approximately
100 m. Even a malfunction of this circuit due to
a short circuit or interruption is not hazardous,
since in this case the heating voltage is reduced
and all other operating voltages are switched off.
The tube is heated by means of inverse current
limiting, thus ensuring a long service life.
)
All values for non-condensing humidity. The values are
1)
valid for clean and well-looked-after microphones or
)
microphone capsules, respectively. Any kind of pollution
of capsules and membranes may restrict the said values.

at 1 kHz into 1 kohms rated load impedance.
)
) Polar patterns: omni/cardioid/figure-8
re 94 dB SPL
4)
)
) according to IEC 6068-1;
CCIR-weighting acccording to CCIR 468-, quasi peak;
)
A-weighting according to IEC 6167-1, RMS
THD of microphone amplifier at an input voltage
6)
equivalent to the capsule output at the specified SPL.
9. Selected Accessories*
(see photos in appendix)
Elastic Suspension
EA 170 .....................ni .................Cat. No. 00771
Auditorium Hanger
MNV 87 ....................ni .................Cat. No. 006804
Popscreen
PS 1 ........................blk ...............Cat. No. 00847
PS 0 a ....................blk ...............Cat. No. 008488
Power Supply
N 149 A EU ..............blk ...............Cat. No. 008447
N 149 A US ..............blk ...............Cat. No. 008446
N 149 A UK ..............blk ...............Cat. No. 008448
Connecting Cable
IC  mt (10 m) ..........blk ...............Cat. No. 0064
KT 8 (10 m) ..............ni .................Cat. No. 008407
Adapter Cable
AC  (0. m) ................................Cat. No. 006600
Meaning of color codes:
ni = nickel, blk = black
* Detailed descriptions and additional articles can be found
in our accessories catalog or at: www.neumann.com
EN