- Large-diaphragm Cardioid Tube Condenser Microphone.
From the Manufacturer
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The M 147 Tube is a vacuum tube condenser microphone with
cardioid characteristic. At the heart of this microphone is the K
47 dual diaphragm , inherited from this model's now
legendary predecessors, the U 47 and the M 49.
Following the is a tube that functions as an impedance
converter. The next stage is an efficient, transformerless output
circuit, that guarantees an extremely low self-noise level. Note:
This innovative combination of current tube technology with the
most advanced solid-state circuitry was decisive in awarding the
1997 TEC Award to the related M 149 Tube mic.
The M 147 Tube can feed extremely long microphone cables without
affecting the quality of the audio signal. Like all Neumann tube
microphones, the M 147 Tube comes with an elegant satin nickel
finish.
The microphone is delivered as a complete set in a high-quality
aluminum case. Included with the microphone are a microphone
cable, a metal swivel for a mic stand, and a compact
universal power supply for standard mains sockets. Our modern
manufacturing methods makes it possible to offer this complete
set at a very attractive price.
Applications
The famous , together with complimenting tube
characteristics, makes the M 147 Tube especially well suited as a
vocal mic. In addition, it is a superb spot mic for all types of
musical instruments. The extremely low self-noise of its tube
circuitry makes the mic perfectly suited for use in modern
chains, analog and digital.
Acoustic features
The M 147 Tube is addressed from the side, where the microphone
body has the diamond-shaped Neumann company logo. The black color
identifies tube microphones. The is equivalent to the one
used in the U 47, and is the deciding factor in determining the
sound characteristic. It has a flat frequency response to the
upper midrange, and a boost of up to 3 dB above 2 kHz. The
headgrille design is a smaller version of the U 47. It protects
the effectively against popping and wind noise.
Polar pattern
The M147 Tube has a cardioid characteristic, leaning more toward
super-cardioid due to its distinctive design. At higher
frequencies the pattern becomes more directional. This is very
similar to the model after which this new tube microphone was
patterned, the U 47 and the successor, the U 47 fet.
Electrical features
When compared to other microphones, the impedance converter used
in the M 147 Tube is distinguished by its extremely low
self-noise level of only 12 dB-A / 24 dB CCIR weighted.
Similar to the recently introduced M 149 Tube, the new M 147
Tube combines a specifically selected vacuum tube (triode) with
modern circuitry. This technique takes full advantage of the
special transfer characteristics of the tube and passes the
processed audio signal of the to the microphone output,
without any coloration or unwanted side effects.
The tube amplifies the 's signal by approximately 10 dB,
thus preventing any possible influences from subsequent
electronics. The M 147 Tube delivers a high output voltage, and
therefore can feed microphone cables up to 300 m length without
signal degradation.
The ideal operating conditions (anode current, heater voltage)
of the tube are maintained throughout its life expectancy. A
sensor lead detects any voltage drop that occurs through the
microphone cable and compensates for it in the N 149 A power
supply. The tube warms up gradually using inverse current
limiting to guarantee long life.
Filter
The electronic circuitry of the M 147 Tube mic has a flat
frequency response from 20 Hz to well above 20 kHz. Only the
attributes of the determine the typical sound
characteristics of the microphone.
Operational Stability
Both, the and the entire circuitry are shock ed to
prevent any structure-borne noise. Because of its wide operating
range, the M 147 Tube can reproduce extremely low frequency
signals without distortion.
This implies that the microphone may also be sensitive to
unwanted LF interference by structure-borne noise, or wind noise.
To avoid possible signal degradation, we offer the EA 1 elastic
suspension and the WS 87 windscreen as accessories. During close
miking of vocals we recommend using the PS 15 or PS 20a pop
screen.
N 149 A Power Supply
The N 149 A universal power supply works with all mains AC
voltages from 100 V to 240 V, 50 or 60 Hz. Mains power is
connected through a standard IEC 320 mains socket. The only
difference between the three available versions of the M 147 Tube
set is the power cord supplied. Note: The N 149 and N 149 V power
supplies that come with the M 149 Tube are fully compatible with
the M 147 Tube microphone.
Features:
* Universal tube microphone
* Pressure gradient transducer with the large diaphragm
from the legendary U 47 and M 49
* Transformerless circuitry
* Low self noise level
* Comes with swivel stand made of metal, universal power
supply, and cable in an attractive aluminium case Applications
* Vocalist mic: its warm and yet transparent sound gives volume
and presence
* Announcer's mic for broadcasting dubbing, and voice-over
* Spot mic for close miking of solo instruments, especially:
strings, wind instruments, and piano These are just some of the
most common applications. We recommend additional experimentation
to gain maximum use from this microphone. Specificatiosn:
* Acoustical operating principle: Pressure gradient transducer
* Directional pattern: Cardioid
* Frequency range: 20 Hz...20 kHz
* Sensitivity at 1 kHz into 1 kohm: 20 mV/Pa
* Rated impedance: 50 ohms
* Rated load impedance: 1000 ohms
* Equivalent SPL CCIR 468-3: 24 dB
* Equivalent SPL DIN/IEC 651: 12 dB-A
* S/N ratio CCIR 468-3: 70 dB
* S/N ratio DIN/IEC 651: 82 dB
* Maximum SPL: 114 dB for THD <0.5 %; 134 dB for THD <5 %
* Maximum output voltage: 8 dBu
* Dyn. range of the mic. amplifier: 102 dB for THD <0.5 %
DIN/IEC 651: 122 dB for THD <5 %
* Supply voltage: Power supply N 149 A
* Matching connector: Microphone: DIN 8F
* Power Supply: XLR 3F
* Weight: 460 g
* Diameter: 57 mm
* Length: 142 mm