KEM 970

Cardioid Plane Microphone
with non-rational symmetry
  • multi-cabsule 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 difusse 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


    papstThe Cardioid Plane Microphone is a multi-capsule microphone system with a unique directional characteristicsthat 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.

    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 neighbouring unwanted noise

    Initial experience gained from practical applications in TV production, stage-sound reinforcement and presenter amplification at lecterns, confirms the fundamental theoretical benefits of the Cardioid Plane Microphone across a wide range of varied applications.


    logo_irt_schrift_trans_2The KEM 970 was developed in cooperation
    with the Institut für Rundfunktechnik (IRT) in Munich.



    The particularity of the KEM 970 is the characteristic that the directional distribution of the sensitivity is a non-rotational-symmetrical pattern in relation to the reference axis.



    cross section


    ground plan


    Application as a table microphon


    Table mounting the KEM 970 as in Fig. 4 allows microphone the to reject unwanted noise or reflections generated by the table surface.



    Comb filter effects generated by table reflections, or paper rustling noises from the desk, etc. are all attenuated significantly. Also apparent from Fig. 4, is the microphones’ immunity to sound from overhead or ceiling mounted sound reinforcement loudspeakers in the vicinity of the presenter. This significantly raises the threshold of feedback, providing much greater resistance to howl-round.



    Application at the speakers stand


    With the KEM 970 positioned as shown in Fig. 4, the presenter has much greater distance and lateral freedom of movement, without the normally attendant quality problems that could be expected with conventional microphones.

    Animated speakers are therefore unlikely to move outside the coverage area of the KEM 970. The low sensitivity of the microphone to off-axis disturbances, such as rustling of manuscripts on the desk, or reflections from the surface is a welcome advantage. Sensitivity to adverse influences from overhead sound reinforcement installations is effectively reduced compared with conventional microphones.

    As an emergency backup, a second KEM 970 can be mounted on the other side of the desk. When two microphones are mounted symmetrically on either side of the desk, the view of the speaker from the auditorium or a camera is not impaired. By contrast, the conventional arrangement of multiple microphones often compromises the view considerably.

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    application for interactive video conferences, live conferences



    Application on the stage


    As an example application, one or more KEM 970 microphones can be placed on floor stands near theedge of the stage, directed towards the area occupied by the actors.If the configuration shown in Fig. 3 is used, then undesirable noise emanating from the stage floor isconsiderably reduced.

    If a sound reinforcement system is in use, the highly directional sensitivity of the KEM 970 on a single axis also adds increased immunity to feedback when compared to other commonly used microphones.

    It is easy to imagine a numerous other applications for the KEM 970, such as creating acoustic effects inradio drama production. Different acoustic scenes can be simulated by an actor changing position aroundthe areas of varying sensitivity to influence the ratio of direct to diffuse sound.

    MA 97.2 Auditorium hanger for KEM970



    Cardioid Plane Microphone KEM 970, non-rotational-symmetrical directivity
    Directional characteristic horizontal super cardioid
    vertical club shaped
    Pick - up recording angle horizontal 120°
    vertical 30°
    Acoustical operating principle Pressure gradient transducer
    Frequency range 40 - 18000 Hz
    Sensitivity at 1 kHz Switch position ”line” 775 mV/Pa
    Switch position ”reduced bass roll - off” at 90 Hz -10 dB
    Rated impedance 40 Ω
    Equivalent loudness level
    due to inherent noise
    CCIR 468-4 24 dB
    DIN EN 60651 15 dB A
    Signal-to-noise ratio
    (re 1 Pa at 1 kHz)
    CCIR-weighted 70 dB
    A-weighted 79 dB
    Max. SPL for THD 0,5 %
    switch position: line
    -10 dB
    -20 dB
    116 dB
    126 dB
    136 dB
    Connecting plugs
    7-pin Tuchel built - in flange plug,
    goldplated contacts
    Finish satin nickel, dark bronze
    Power supply N 970 / N 970 D
    Power supply voltage 230/115 V AC ± 10 % 50/60 Hz
    Connecting plugs Tuchel built - in flange box T 3463.000
    XLR built - in flange plug SWC D3M
    Dimensions / Weight
    Microphone (L x Ø ) 355 x 40/25 mm / 0,96 kg
    Power supply unit N 970 / N 970 D 190 x 127 x 90 mm / 1,8 kg
    Microphone connecting cable with swivel mount, C 97 S 10 m / 1,1 kg


    Frequency Responses



    Polar Patterns



    Cardioid Plane Microphone KEM 970, in Suitcase 2 - Aluminium
    L x B x H   450 x 160 x 365 mm
    Power supply N 970 or
    Power supply N 970 D,      optional: output digital - AES/EBU - DPP
    Microphone cable C 97 S with swivel mount
    satin nickel
    Order-No. 211149





    Cardioid Plane Microphone KEM 970, in Suitcase 2 - Aluminium
    L x B x H   450 x 160 x 365 mm
    Power supply N 970 or
    Power supply N 970 D,      optional: output digital - AES/EBU - DPP
    Microphone cable C 97 S with swivel mount  
    dark bronze
    Order-No. 211159





    finishing on customers request 



    INV-BH Order-No. 600138
    elastic suspension Rycote INV-BH 

    KEMRycote kl

    W97 Order-No. 202411
    Windscreen for KEM970, 2 parts
    MH97 dark bronze
    Order-No. 202334

    Microphone holder for KEM970
    stationary fixing, 3/8", 1/2"



    MH97 satin nickel
    Order-No. 202333

    Microphone holder for KEM970
    stationary fixing, 3/8", 1/2"

    MH97.1 dark bronze
    Order-No. 202336

    Microphone holder for KEM970
    elastic-stationary fixing M10



    MH97.1 satin nickel
    Order-No. 202335

    Microphone holder for KEM970
    elastic-stationary fixing M10

    MA97.2 dark bronze
    Order-No. 202353

    Auditorium hanger for KEM970


    MA97.2 satin nickel

    Auditorium hanger for KEM970

    C 97.1
    Order-No. 202207
    Connection cable for KEM970; 10m, Tuchel 7-pin
    C 97.2
    Order-No. 202208
    Connection cable for KEM970; 20m, Tuchel 7-pin
    C 97.3
    Order-No. 202209
    Connection cable for KEM970; 30m, Tuchel 7-pin
    C 97S
    Order-No. 202205
    Connection cable for KEM970; 10m, Tuchel 7-pin, with swivel mount


    Prospect KEM 970



    Prospect MA 97.2



    Manual MA 97.2




    Mehrkanal - Kondensatormikrofonsystem
    Erfassung weit ausgedehnter oder sich bewegender Schallquellen
    ca. 3 facher Aufnahmeabstand bei gleichem Diffusfeldanteil
    gegenüber Kugelmikrofonen
    optische Anzeige für optimalen Aufnahmebereich
    Unterdrückung unerwünschter Reflexionen vertikal zur Einsprechrichtung
    Erhöhung der Rückkopplungsgrenze bei Beschallung um 6 dB
    Übertragungsbereich 40 - 18000 Hz
    line - Pegel Ausgang, Pegelabsenkung 2 stufig
    Ausgang: analog oder digital - AES/EBU - DPP