Eliminating Feedback in Your Auditorium

Feedback is a common problem that most AV teams will face at times, and it often comes at the worst moments. In order to know how to respond and eliminate the feedback, it is helpful to understand what it is, what causes it, and how the solutions affect the problem.

What is feedback? Feedback is the uncomfortable ringing or squealing that comes over your loud speakers, often getting louder and more uncomfortable until it is addressed.

What causes feedback? Feedback occurs when the amplified sound from your loud speakers goes into one of your microphones, comes out the loud speakers and back into the microphone again. The sound increases as it creates a loop of intensifying ringing. You can think of it as a mirrored image of a mirror in which the mirror is reflected infinitely. The sound in feedback is that infinite repeat of sound circling through your audio system.

How do I stop feedback? Feedback can be reduced and eliminated in several different ways. We have included for you here a few suggestions for both immediate and long-term solutions.

  1. Reduce the volume of the loudspeakers. When feedback occurs in the middle of a service or performance, this should be your first step, as it will stop the sound loop and help you regain control.
  2. Turn off microphones not currently in use. It can be difficult at times to pinpoint which microphone and speaker/monitor is creating the feedback, so it is a best practice to mute and unmute microphones as needed.
  3. Encourage those speaking or singing to get closer to their microphones. The further away the subject is from the microphone, the louder they have to be turned up, inviting a chance for feedback.
  4. Ensure that all of your loudspeakers and monitors are properly positioned. Make sure that no speakers or monitors are pointed at microphones or at flat sound-reflecting surfaces and move all speakers and monitors as far away as possible from microphones. Additionally, hang the house speakers closer to the audience.
  5. Install appropriate acoustical treatment in the room. This can include curtains, acoustical panels, architectural details, etc. When your auditorium has good acoustics, you will not have to worry about reflected sound into your microphones.
  6. Consider in-ear monitors, rather than floor monitors. By allowing your singers to have in-ear monitors, you greatly reduce the amount of sound that is on stage and therefore greatly reduce chances for feedback.
  7. Hire an AV company to EQ (tune) your sound system. Every auditorium is unique and will have unique audio needs. By hiring a company like AdvanceTech Systems to tune all of your microphones, you will be able to eliminate the frequencies in your facility that cause consistent feedback.

As always, if you have any questions or would like help eliminating feedback and creating a better sound in your auditorium, contact us at any time.