Hello Jim and welcome to the Cow Audio Forum,
You have done some good problem solving. You pretty much have your answer, it’s the mixer.
Now, why?
Do you have the 48 V DC option for the mixer? If not, the likely cause is the 18 V DC Phantom Power voltage. Sennheiser 416 mics require 48 V DC Phantom Power. If they don’t get it, they sound distorted because they are power starved.
Even if you do have the 48 V DC option, the power supply may not have the current to power the 416 properly. Power of any sort is a function of voltage and current – actually power TIMES current. The formula is P=IE; where P is power, I is current and E is voltage.
There are outboard, battery-powered Phantom Power supplies that do supply 48 V DC at a current level high enough to power the MKH 416.
If you were paying me to consult with your on your sound package, I would spec the Sound Devices 302 mixer to replace the Marenius. If your transmitter can take line level input, the Sound Devices MixPre works. It’s lighter and is more easily belt mounted than the 302. BTW, I’ve never heard of Marenius. Thanks for letting us know about them.
Regards,
Ty Ford
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