Rodney, if you’re crazy, I’m crazy. You’re one of the brighter guys here at Cow and I really appreciate that you’re here.
You make an excellent observation. Technically, what you’re talking about is some sort of distortion that happens when a frequency range larger than expected is put through a system not designed to handle it.
It may be just the mic itself or something in the circuitry of the transmitter. I don’t think it’s happening in the receiver, but it’s not impossible.
I occasionally run into sub-harmonic problems with my wireless. We were going from one location to another at NASA/Greenbelt last month. I was fully rigged with mixer, two lavs and a boom, had my headphones on was listening to the wireless. While we stood waiting for the elevator, the meter on my Sound Devices 442 mixer started showing something and I was hearing the compander in one of the wireless get a little wacky. I took off my headphones and I could hear/feel this very low frequency resonance; the kind you get in some buildings. I’m not sure what the source was, but this sort of structure-born sound can play havoc with a wireless system.
I’ve even run into it outside. It isn’t usually constant, but something somewhere made a noise and the waves roll out from it. It the same thing when you’re sitting still on a boat and another boat goes by. Eventually their wake will pass under you.
If I had mics with a high-pass filter to scrape that stuff off, it wouldn’t have modulated the compander threshold.
Not all wireless are the same, Adam. What you may have found might be the Achilles Heel of the Sennheiser system. Maybe they didn’t design it to be used near a sound source like a piano. In trying to get the circuit right for voice, they might have ignored the possibility that the system would be used around a piano.
Or, (now for something completely different) I have heard that the ME2 lav that comes with the G2 wireless is not so good. People have said that trading up to a MKE2 made a noticeable improvement. They weren’t even talking about piano.
Rather than condemn the transmitter, I’d be interested to hear if the problem went away if you tried a different lav. The MKE2 is good. Other very good lavs are the Countryman B6, EMW and Sanken COS11. You can order the Countryman mics with the right plug to work on the Sennheiser. I suspect you can do the same with the Sanken.
There are a few hinky (two wire or three wire) wiring problem that do exist among mics and transmitters, but a knowledgeable shop should know about that.
I have EMW and B6 mics and I had them made with cables so that I could switch and use the mics with my wireless or connect them through an inline XLR power supply and use them hard wired. Sometimes hardwired is the easiest way to go.
Hope this helps and do let us know what you find.
Regards,
Ty Ford
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