Setting Up Your SystemFeedback
Feedback results when the amplified sound hits the microphone at nearly the same volume as the source. You are generating a sound wave which is picked up by the microphone, amplified by the sound system, picked up again and amplified more by the sound system and so on. It is characterized by howling from the speaker or a ringing noise.
The easy cure for microphone feedback is to turn down the volume. The feedback goes away but now everyone can’t hear what you are saying. The better approach is to set up the system so feedback is prevented in the first place. What you are trying to do is get more gain from the system.
Gain is the difference (in sound level) between the original source and the amplified signal. For example, an audience member is sitting 35 feet from you. You are speaking without an amplifier. The audience member hears the sound at 65dB. When the system is turned on, you are heard at 77dB. 77 minus 65 is 12. That is a gain of 12dB.
A decibel is a measure of sound that is based on proportional measurements and is logarithmic in nature. To get 3dB more gain is equal to doubling the sound level. Although 12dB doesn’t sound like much of an increase, it is 16 times louder. The whole idea is to get as much gain from the system as possible without feedback.
Download entire Wireless Sound System Setup Guide Here.