Hi Kevin,
If you are using 6 Sennheiser ew 300-2 IEM G3 transmitters will they work just fine with the provided antennas all racked up together or do you really need an antenna combiner? They will probably be only about 40 feet away from the receivers. But I am more concerned with the intermods that might be created, like if you put a bunch of wireless mic transmitters all next to each other.
You are wise to be concerned about intermods in this scenario, as they are very likely to occur. Many people set them up like this and have no trouble, but the problem is that they can work fine until they
don't one day. Then you will have a very unhappy performer, audience, and client, and few options to solve the problem. Using a proper IEM combiner from the start, as in any situation where doing the job right vs. winging it, will drastically lower your chances of having trouble with the system and will narrow your range of possible issues when it comes time to troubleshoot.
I am trying to convince the person who this relates to that he would be better to just put each transmitter on the same stand as the personal mixer that will be feeding each transmitter. And along these lines how would it be to be that close to the transmitter. I have seen problems with a wireless receiver in a pulpit when the person wearing the transmitter gets too close. Is it the same with the IEM setup?
This is an excellent way to deploy such a system when on a tight budget and trying to keep it simple. RF overload can occur in IEM receivers, but it is not as prevalent a problem with "off the shelf" setups as many people think. Senny G3's are relatively low power transmitters, with the choice of 10mW and 30mW outputs. IMHO, you must get the receiver
very close to a 10mW transmitter with a whip antenna to have audible overload problems. One easy way to deal with this is to simply place the IEM pack on the opposite side of the wearer's body from the transmit antenna's location, at the area where the wearer spends most of their time while performing.