of the Sennheiser condenser microphones with
Senn heiser condenser microphones produce relatively large output voltages, these can be up to 1 volt with maximum sound pressure levels. This has the advantage that even with long cables induced interference signals can be disregarded. Also the internal
noise produced by the microphone does not contribute to the total noise level. The mi-
crophones are fitted with high frequency filters, which ensure that no high frequency signals from the microphone can affect the external circuitry, and also that the microphone itself is protected from~high frequency
disturbance. It is, therefore, not necessary, even under the most difficult conditions, to
take special precautions such as double screening of the cables or the provision of high frequency filters.
Sennheiser condenser microphones are po- larised according to DIN standard ie. when
apressure signal strikes the capsule from
the front, Pin 1 goes positive with reference to Pin 3. This should be considered when
the amplifier input plug is being wired.
Connection to amplifiers with symmetrical inputsIn this case the microphone is simply connected via the battery adapter MZA
supply MZN 6, which can feed up to six mi- crophones, can be used. In this case it
should be noted that the power supply is delivered without feed resistors and these
must be added by the user.
Connection to amplifiers with unsymmetrical inputsIn many cases, for example most tape re- corders, the input socket is unsymmetrical. In this case one side of the symmetrical microphone output has to be earthed. Apart from cases where the microphone is being used for professional studio purposes, this is not critical, as the large output voltage of the microphone combined with its low output impedance provides a large signal to noise ratio. Care should be taken, however,
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