This is a special order item, please allow 2-4 weeks for delivery.Includes:
- 2 Microphones KM 150
- 2 Connecting cables LC 3 KA
- 1 Stereo mount STH 100
- Wooden box
The variable
condenser miniature
microphone system consists of several active
microphone capsules with different
directional characteristics, an output
stage, and numerous accessories.
Currently there are seven active capsules available: omni diffuse-field equalized, omni free-field equalized,
cardioid, wide-angle
cardioid,
cardioid with
bass roll-off,
hypercardioid, and
figure-8.
Through the modular construction of
mic capsules and the output
stage it is very easy to adapt the system to a wide range of applications. The
mic becomes nearly invisible during work with cameras (film,
video), on
stage, or suspended from the ceiling in a concert hall.
An active
capsule can also be screwed directly onto the output
stage. The result is a compact miniature
microphone.
ConstructionThe microphones are only 92 or 110 mm resp. long and 22 mm in diameter. They consist of the
condenser capsule and the output
stage. Both parts can be unscrewed from each other. The system offers several
condenser capsules with different
directional characteristics.
Numerous accessories can be mounted between the capsules and the output
stage. The capsules attach to cables,
capsule extensions, swivel mounts, table stands, goose-necks,
stereo mounts, and hangers. Therefore, it is very easy to adapt the system to a wide range of applications.
The active
capsule itself is only 35 or 47 mm resp. long. The
KM 100 output
stage and the active
microphone capsule may be separated by up to 50 m of interconnecting cable. These cables are 3 mm in diameter, and therefore very inconspicuous.
Acoustic featuresAK 20 is a pressure gradient
transducer with the
figure-8 characteristic, realized with a single
diaphragm. The
diaphragm diameter is just 16 mm. All
sound field components reach the
diaphragm directly. This results in identical
frequency response curves and output levels at 0 and 180
sound incidence. Corresponding accessories allow combining the
AK 20 with other active capsules or microphones to obtain an MS-
Stereo setup.
AK 30 is a diffuse-field equalized pressure
transducer with a flat
frequency response up to 10
kHz (in the diffuse field). In the free
sound field this
microphone has a boost of approximately 7
dB at 10
kHz.
AK 31 is a free-field equalized pressure
transducer with a flat
frequency response up to 20
kHz (in the free field). In the diffuse
sound field this
microphone has a high
frequency roll-off above 5
kHz.
AK 40 is a pressure gradient
transducer with
cardioid characteristic. The
frequency curves are very smooth and match 0
sound incidence.
Sound from sources within a pickup angle of +/- 135 is reproduced without any
coloration.
AK 43 is a pressure gradient
transducer with wide-angle
cardioid characteristic. Attenu- ation at 90 is 4
dB, at 135 it is 8
dB and at 180 it is 11
dB. The
frequency response curves for
sound sources within an angle of +/- 90 are parallel up to 12
kHz.
AK 45 is a pressure gradient
transducer with
cardioid characteristic, similar to the
AK 40. However, it has an acoustic
bass roll-off that is useful during applications when subsonic and low frequencies may cause difficulties. The AK 45 is optimized for a flat low
frequency response at a recording distance of 15 cm ("speech
cardioid").
AK 50 is a pressure gradient
transducer with
hypercardioid characteristic.
Attenuation of
sound incidence from the side or rear is about 10
dB, with minimum
sensitivity at an angle of 120.
Electrical featuresThe
KM 100 is phantom powered (48 V) and uses transformerless output circuitry. This has several advantages. It features high output capability and extremely low
self noise. It provides exceptionally clean
sound, free of any
coloration. As with traditional transformers, this circuit approach ensures good common mode rejection. The
balanced output signal is protected against interference.
The construction is extremely compact. The entire
microphone circuitry is on a single hybrid module measuring only 2 cm(2) in area. It is built into the
microphone capsule, therefore the term "active capsules".
All sensitive components are protected within the
capsule. As a result, the quality of the
audio signal is never compromised through the use of accessories, for example, when the
capsule is detached from the output
stage and mounted on a cable or a
gooseneck.
Even with a long cable between active
capsule and output
stage, the signal is immune to external interference.
PreattenuationThe output
stage has a 10
dB switch.
Attenuation is achieved by reducing the
capsule voltage to one third.
When the switch is on, the
microphone is capable of accepting
sound pressure levels up to 150
dB without being overloaded.
ConnectorsTo diminish the number of connectors within the
KM 100 System some accessories were modified. They can now be screwed directly onto the
KM 100 output
stage without using the
KA 100 cable adapter. The new accessories which include the cable adapter, were renamed adding the suffix KA. For example: LC 3 is now LC 3 KA.
The separate
KA 100 cable, needed for older accessories, will be available also in future.
The
KM 100 output
stage has a 3-pin
XLR connector.
Sound diffraction sphereThe SBK 130
sound diffraction sphere slips onto the front of the KM 130/KM 131 pressure microphones. The
diaphragm becomes an integral part of the surface of the sphere. This affects the
frequency response of the microphones.
While sounds coming from the front-half space are emphasized by up to 2.5
dB between 2
kHz and 10
kHz, sounds arriving from the rear-half space are attenuated by a maximum of 2.5
dB in the range above 5
kHz.
Since the
sound diffraction sphere causes the pressure buildup of the KM 130/KM 131 pressure microphones to begin earlier, the
frequency response rises smoothly in the middle and upper range. This is similar to a typical pressure gradient
microphone, where the
directivity increases with rising frequencies. However, since the KM 130/KM 131 are pressure microphones, they maintain a linear
sensitivity down to the lowest frequencies.
This changing
directivity allows to record at a greater distance from the
sound source, and makes the KM 130/KM 131 microphones especially suited as
stereo main microphones in A-B configurations.
KM 100 F Output stageThe
KM 100 F output
stage is an alternative to the
KM 100 output
stage. In contrast to the
KM 100 output
stage with a flat
frequency response, the
KM 100 F attenuates frequencies below 80
Hz at 6
dB/
octave. This eliminates or suppresses interference caused by wind or structure-borne
noise.
A built-in slide switch allows to raise the cut-off
frequency (-3
dB point) from 80
Hz to 120
Hz. An additional slide switch lowers the
sensitivity by 10
dB.
Stereo recordingsBy means of the
AC 30 adapter cable two active capsules,
AK 20 and e.g.
AK 40 can be connected as
MS stereo pair directly with the MTX 191 (A) matrix
amplifier. The
XY or
MS signal is then available at the 5-pin
XLR output connector of the MTX 191 (A), and the recording angle can be electrically remote controlled. The output stages
KM 100 are then not required.
Stereo setThe
cardioid and
hypercardioid microphones are also available as complete
stereo sets,
SKM 140 and SKM 150, including all accessories in a single jeweler's box.
A further
SKM 100-MS Stereo Set containing the microphones KM 120 und KM 140 is available.
Features:
- Miniature microphones with 7 exchangeable capsules
- Active capsules, detachable up to 50 m from the output stage
- Great variability through capsule extensions and goosenecks
- Switchable 10 dB preattenuation
- Set includes windshield and two different clamps
- Transformerless circuitry
- Extensive accessories
Specifications:
- Acoustical operating principle: Press. grad. transducer
- Directional pattern: Hypercardioid
- Frequency range: 20 Hz ... 20 kHz
- Sensitivity at 1 kHz into 1 kohm: 10 mV/Pa
- Rated impedance: 50 ohms
- Rated load impedance: 1000 ohms
- Equivalent SPL CCIR 468-3: 27 dB
- Equivalent SPL DIN/IEC 651: 18 dB-A
- S/N ratio CCIR 468-3: 67 dB
- S/N ratio DIN/IEC 651: 76 dB
- Maximum SPL for THD 0.5%: 142 dB
- Maximum SPL for THD 0.5% with preattanuation: 152 dB
- Maximum output voltage: 10 dBu
- Dyn. range of the mic. amplifier DIN/IEC 651: 124 dB
- Supply voltage: 48 V +/- 4 V
- Current consumption: 2 mA
- Matching connector: XLR 3F
- Weight: 80 g
- Diameter: 22 mm
- Length: 92 mm