The Petra Zone

Why do singers have ear plugs in their ear? What are they listing too?

Those are IEMs (In Ear Monitors). There are two types, wired and wireless. Having IEMs allows the performers to hear a better mix of what they need to hear, as opposed to using monitors on stage. This reduces the stage volume, cleans up the stage mix, and allows the FOH (Front of House) engineer to mix a better mix for the crowd.

The better IEMs are custom molded, fitted by an audiologist. The cheaper ones are universal, do not fit well, and allow for leakage.

When you hear singers sing flat or sharp, they are listening too low or too loud. That is how our auditory system works. IEMs can cause ear infections when they are not cleaned religiously. They can also cause more hearing damage than wedges, because you can always move out of the line of fire or a monitor.