Re: safe way to connect wireless to output from sound board

From the information available on the Sennheiser website, there are two different lines of transmitters. There are transmitters intended for use with microphones (body pack as well as plug-on), and then there are transmitters designed for use with musical instruments (like electric guitars, etc.) It appears that only the instrument transmitters have the built-in pad on the ring terminal. It appears that the microphone transmitters (which you seem to have) do NOT have a built-in padded input, so they DO require attenuation external to the transmitter. It sounds like the cable you mentioned (which has no attenuation) is intended for use only with the instrument transmitters (which you do not have).

NOTE: I am trying to interpret the sparse information on the Sennheiser website and from 3rd party sources. I do not have (and have never used) a Sennheiser instrument transmitter, so I have no first-hand experience with this. Of course, since you have your transmitter(s) and you have the cable, you are in a perfect position to do the actual experiment with the actual equipment. If you start with a very low-level (mic level) signal and slowly increase it, you won't damage your transmitter during the experiment.