Neumann.Berlin M 147 Tube Instruciones De Operacion página 3

6. Shutdown and storage
Before switching o the microphone or discon-
necting the cables, reduce the volume of con-
nected equipment.
Only then should the power supply equipment be
switched o .
Disconnect the cables.
When disconnecting a cable, always pull only on
the connector and not on the cable itself.
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 the
subsequent equipment.
8. Technical data and
connector assignments
Permissible atmospheric conditions: 1)
Operating temperature range ............0 °C ... +70 °C
Storage temperature range ............–20 °C ... +70 °C
Humidity range ..................... 0 % ... 90 % at +20 °C
0 % ... 85 % at +60 °C
Acoustical op. principle .............Pressure gradient
Directional pattern .....................................cardioid
Frequency range ...............................20 Hz...20 kHz
Sensitivity 2) ...............................................20 mV/Pa
Rated impedance ........................................50 ohms
Rated load impedance ..........................1000 ohms
Signal-to-noise ratio ,
3)
CCIR 4) .............................................................. 70 dB
Signal-to-noise ratio 3) ,
A-weighted 4) .....................................................82 dB
Equivalent noise level,
CCIR ................................................................24 dB
4)
Equivalent noise level,
A-weighted 4) ................................................. 12 dB-A
Max. SPL (tube characteristic) 5)
for THD < 0.5 % ..............................................114 dB
for THD < 5 % ................................................. 134 dB
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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 atmos-
pheric conditions, and should be protected
from dust. For this purpose, use a lint-free, air-
permeable 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.
Max. output voltage ........................................ 8 dBu
Power supply ............................................... N 149 A
Required connectors:
Microphone ....................................................DIN 8F
Power supply unit ..........................................XLR 3F
Weight ............................................................. 460 g
Dimensions ................................Ø 57 mm x 142 mm
94 dB SPL equiv. to 1 Pa = 10 bar
0 dB equiv. to 20 Pa
transducer
The 8-pin connectors of the microphone and
the power supply unit have the following pin
assignments:
Pin 1: –70 V
Pin 2: +5 V
Pin 3: Modulation (+phase)
Pin 4: +70 V
Pin 5: Sensor line
Pin 6: Ground
Pin 7: +32 V
Pin 8: Modulation (–phase)
The 3-pin XLR output of the power supply unit has
the following standard pin assignments:
Pin 1: 0 V/Ground
Pin 2: Modulation (+phase)
Pin 3: 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 o .
The tube is heated by means of inverse current
limiting, thus ensuring a long service life.
1) All values for non-condensing humidity. The values are
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.
2)
3) re 94 dB SPL
according to IEC 60268-1;
4)
CCIR-weighting acccording to CCIR 468-3, quasi peak;
A-weighting according to IEC 61672-1, RMS
5) THD of microphone amplifier at an input voltage
equivalent to the capsule output at the specified SPL.
9. Selected Accessories*
(see photos in appendix)
Elastic Suspension
EA 1 ..........................ni .................Cat. No. 008449
Auditorium Hanger
MNV 87 ....................ni .................Cat. No. 006804
Mount
SG 1 ..........................blk ...............Cat. No. 008445
Popscreen
PS 15 ........................blk ...............Cat. No. 008472
PS 20 a ....................blk ...............Cat. No. 008488
Windscreen
WS 87 ......................blk ...............Cat. No. 006753
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
KT 8 (10 m) ..............ni .................Cat. No. 008407
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
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