Feedback is an issue that virtually every church battles with.
In the last article we talked about some of the causes; here we will talk about a few ways to deal with it.
If your problems are pervasive and an acoustician was either not involved in the design, or their recommendations were ignored, it's worth having an acoustics consultant check out your room and see if that's adding to your problems.
However, especially for historic churches, treating the room for acoustical issues may not be aesthetically acceptable.
If you're not willing to add acoustical panels to your walls or other visible changes to the architecture, this may be a waste of time.
Some feedback issues are cause by having too many microphones open (unmuted) at one time.
If you are having feedback issues, it's critical to only have microphones turned on when you need them. If someone isn't speaking right at that time into the podium mic, it should be muted. If your vocalists aren't singing right now, mute them. If your pianist isn't playing right now, mute the piano mics. And so on.
If you have a pastor that likes to roam the room, and they normally wear a lavaliere microphone clipped to their shirt or tie, switch them to a head-worn microphone which puts the microphone right at the corner of their mouth.
Each time you cut the distance from the mouth to the microphone in half, you increase by 3 dB your gain before feedback.
With a lavaliere mic, the distance is about a foot. With the head-worn mic, the distance is about an inch or less. That amounts to a 10+dB increase in gain-before-feedback, which is substantial, and should greatly help with any feedback issues with your pastor's mic.
Likewise, make sure your vocalists are holding their mics close to their mouths. We are trying to pick up the sound from their mouth not the sound of the sternum, and certainly not the belly button!
For microphones that are problematic, you can go through a process called "ringing out" a microphone. We'll talk about that process in the next article.
And lastly, I believe people have this subconscious idea that having a microphone means you can speak softly.
In an ideal room, this may be true. However, rarely is a church sanctuary or auditorium an ideal room.
For anyone using a microphone, they need to be taught proper mic placement (at the mouth, not the belly button), and they need to project. The best thing to do is speak as if you don't have a microphone. They less volume we need to get from the microphone, they less we need to alter the sound from the microphone to deal with feedback, which results in more natural sound and more gain before feedback.