Problem with Shure PGX Wireless

[tonyatan]

hi

I just bought Shure PGX wireless (with Omni Lavalier Microphone). I tried different channel and it's giving a very annoying feedback.

I changed the sensitivity (gain) on the body pack to "Mic" - I set the gain on the mixer very small and the feedback is very high.

I changed the sensitivity to "0", I can hardly hear anything even when I setup the gain very high (75% - 80% of the gain on the mixer).

I do not have the same problem when I use a different bodyback clip microphone (Sennheiser EW 100) on the same channel.

I am wondering if the new Shure PGX wireless is not compatible with the mixer or other sound system. I am quiet new a sound man so any help would be grealy appreciated.

Thanks,

[audiomatic]

Some receivers (the box at the sound booth) have a volume control. It may be that the difference between the Shure and Sennheiser is that one of them has a volume control turned louder or quieter than the other.

Are there monitors on stage? If so, does the feedback go away when the mic is moved offstage? Is the mic intended for singing, or speech only? Maybe you need to take some of that mic out of the monitor(s) if used for singing; take it completely out if used for preaching (the pastor doesn't need to hear himself in the monitors).

Is the feedback high frequency or low frequency? If it's mostly low frequency, cut everything below 100 Hz on that channel (the lowest people can speak or sing is about 80 Hz, so you won't be losing anything). Many mixers have a "low cut" (sometimes called "high pass") button to accomplish this.

[sien]

Hi There,

Are you using the xlr output or 1/4 inch output from the PGX4 Receiver?
The XLR output is mic level out. The 1/4 inch output is line level.

[tonyatan]

@audiomatic
The feedback is high frequency. I have tried to cut the frequencies but still does not help.
We used it for Pastor's sermon so it's mainly speech. We have monitor on stage but we turned it off so don't think the feedback came from speaker monitor.

@sien
I tried to use both (XLR and 1/4") they both the same i.e. feedback.

[pdc]

You really need to have someone come out and take a listen. It could be acoustic and/or electronic feedback caused by the mic/speaker relationship. You could have some wireless system gain issues and system gain issues that could be causing it.