XDV75 Feedback

[halgalardi]

Hey guys.
I am using 7 xdv75 with headset mics in a musical. They're all great, but ONE of the packs has feedback...all the time. After full troubleshooting - I know that it is just the pack. 

Anyone ever have this issue?

 

Love

[Digitalman42]

I know this is a year old, but ....

 

Could it be that the gain on the receiver (for the pack in question) is set higher than the rest?

 

Or, could it be that the vocal EQ filter model on the transmitter is set different from the rest allowing for higher frequencies to pass thru?

 

If you solved the issue, I would be interested in learning what you did.  I'm going to be running a six mic setup and the additive effect of all the open mics on stage can be a feedback nightmare.  I'm looking into gates and feedback destroyers to help eliminate or at least reduce the feedback,

 

 

[Sheriton]

As it's impossible for a mic to feed back all of the time, I suspect what Hal might have been experiencing was simply the pack generating a high pitched whine that sounded like feedback. I recall that's a fault that has occurred before.

 

On the general topic of feedback... The best way to deal with it really depends on the scenario. It starts with the full system design, including placement of speakers and choice of appropriate speakers with polar patterns to suit the application. That stage will head off many issues before they even have the chance to arise. That said, we rarely have the luxury of using the perfect speaker in the perfect position so some electronics are often necessary.

 

If it's a conference type scenario - one person speaking at a time - an auto mic mixer is your best friend. Most digital desks have these built in nowadays and they're also available in external hardware form and software plugin form. They just listen to which person is currently speaking and reduce the gain of all the other mics to intelligently keep the overall gain of the system below the feedback threshold. Properly set up, they work wonders.

 

If it's theatre - musical or otherwise - the standard approach is to mix line by line. Only the person who's currently speaking has their mic open; all others on stage are lower or off. It's second nature to those of us working in theatre but for anyone from a rock 'n' roll background, it seems like very hard work. (And it is!) Careful programming of DCA assignments helps enormously. It's an essential technique to keep background noise low but with the added benefit of avoiding any risk of feedback.