Today's Lesson

Ringing out your room is a process for stabilizing your PA system against feedback by identifying and eliminating problematic frequencies that are prone to feeding back naturally. It’s a simple process that can make a big difference when it comes to controlling feedback. You can use an RTA to help do this faster and more efficiently. Some mixing consoles will have an RTA built in, if not, there are external ones available or you can simply download an RTA app on your smart phone or tablet.

Here’s how you do it:

1. Make sure the microphones on stage are live and gained up properly.
2. Push the fader up on your main output until the system begins to feedback.
   1. Use your RTA to identify the frequency that is feeding back and then bring the fader back down so the feedback stops
3. Now go into the output EQ and bring down the offending frequency. Depending on your mixer, you might have either a graphic or parametric EQ to do this. Some mixers might also have notch filters which are specifically designed to be used to eliminate feedback.
4. Now repeat this process until the system is stable with about 6-10dB of headroom on the main fader. 

For more lessons and videos, see our QSC YouTube page.