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I have a Schoeps CMR mic adapter and it doesn't work with the newer servo input amplifiers. How should it be wired to the 5 pin TA5F?


From the Shoeps web site: "The SCHOEPS CMR microphone amplifier allows any SCHOEPS ”Colette” series capsule (except the BLM 03 C active boundary layer capsule) to be used with pocket transmitters." 

In the email below is the TA5F wiring that works with our older transmitters such as the UM200 and the newer servo style inputs such as the UM400a or the SM transmitters.

Hi Charlie,
The CMR adapter is on its way back to you. The rewiring was pretty simple. The problem was that the CMR adapter doesn't like any DC voltage applied to the audio line (our pin 3). The SM servo unit applies 2 Volts to pin 3 when pin 4 is not wired to ground. With the voltage switched off, the mic sounded great but had too much gain in my opinion. We added a 1.5 k resistor in series with the audio line (our pin 3 again) and now the mic has about the same gain as a COS-11 when used with a UM400a or an SM. It still works with an older transmitter such as a UM400 or UM200 with a few dB more sensitivity than with the SM. If you should want more gain with an SM, reduce the size of the resistor; 500 Ohms = +6 dB.

So here's the final wiring for full compatibility:

  • Schoeps shield to pin 1
  • Pin 4 jumped to pin 1 (shuts off servo bias)
  • Schoeps blue wire to pin 2 (+5 Volts)
  • Schoeps white wire to a 1.5k resitor in series with pin 3 (audio in)
Posted 1 year agoby LectroAdmin