The Cardioid Plane Microphone is a multi-capsule microphone system with unique directional characteristics that are largely independent of frequency.
On the horizontal axis the KEM 970 has the characteristic of a cardioid microphone, whilst on the vertical axis the characteristicsresemble a shotgun microphone with a very narrow acceptance angle of about 30°.
The directional pattern is therefore particularly well suited to the most frequently encountered situations where the source to be recorded is widely spread, or moving across the horizontal plane and sound arriving from other directions needs to be attenuated.
Attenuated sound may consist of unwanted noiseor reflections from surfaces such as ceilings, tablesor the floor. Mounting the microphone physically onits side can significantly reduce feedback problemsfrom sound reinforcement loudspeaker installationson the side walls.
For effective use of the highly directional nature ofthis microphone, a good understanding of thedirections from which wanted and unwanted soundsarrive is important. The more care taken in positioningthe KEM 970, the better the results obtained will be.Integrated front facing indicator lights help inpositioning the microphone accurately.
Acoustic treatment to improve a room can be anextremely costly exercise, and perhaps not even possible when trying to achieve the average 5 dB increase in operating level that the KEM 970 provides.An added benefit of the KEM 970, as shown in Fig.3,is its ability through skilled use of the sensitivity characteristics, to compensate for level changes if the sound source moves closer to the microphone.
Features
Multi-capsule condenser microphone system
Broad cardioid pattern to cover wide or moving sound sources
Locate up to three times the distance of omni microphones for same diffusse field
Optimum positioning using visual indicators
Suppression of undesirable reflections on the vertical axis
6 dB improvement in feedback threshold for sound reinforcement applications
Frequency response 40 - 18000 Hz
Line level output, two position pre-attenuation switch
High pass filter switch
Analog or digital AES/EBU - DPP output
Recommended applications of the KEM 970:
On edges, or ends of stage
At a presenter´s desk
As a table microphone
Radio and TV productions
Video conferencing
Location of neighboring unwanted noise
Specifications
Cardioid level microphone KEM 975, with non-rotationally symmetrical directional characteristics
Directional
Horizontal: kidney-shaped
Vertical: lobar
Angle of coverage
Horizontal: 120 °
Vertical: 30 °
Acoustic operation: Pressure gradient Frequency response: 40 - 18000 Hz Sensitivity at 1 kHz, gain 0 dB: 775 mV / Pa Rated impedance: 40
Equivalent noise
CCIR 468-4: 24 dB
DIN EN 60268-4: 15 dB-A
Noise distance (to 1 Pa at 1 kHz)
CCIR rated: 70 dB
A-rated: 79 dB
Boundary sound pressure level for 0.5% harmonic distortion
Gain 12 dB 104 db
Gain 0 dB 116 dB
Gain -12 dB 128 dB
Gain -24 dB 140 dB
Gain -36 dB 152 dB
End fittings: Neutrik XLR5M Mass: 1.07 kg Length: 343 mm Diameter protection cage: 40 mm Amplifier: 25 mm Surface: Nickel matt, dark bronze
Power supply unit N 975
Mains voltage: 230/115 V AC, ± 10% 50/60 Hz
Connection fittings
KEM 975: XLR5F
Audio signal: XLR3M
Mass: 1.6 kg Width: 221 mm Depth: 169 mm Height: 45 mm
