ST. LOUIS - They are one of the most popular groups in country music: Hillary, Charles and Dave, better known as Lady Antebellum.

A band that has sold more than 10 million albums and performed in places big and small. The thing is bands do things differently for different sized venues like for this private show at River City Casino they used monitors on the stage to hear themselves.

When it's a bigger venue they use an ear piece officially known as an in-ear monitor.

"It's basically like your Earbuds that you listen to music on they're just molded to your ear that's where we hear all the instruments and vocals are coming back through there," explains Dave Haywood, one-third of Lady Antebellum.

"And you can move around an entire arena and still hear what's happening in real time instead of you get a big delay if you were to move through a big arena and not have those in," adds Hillary Scott, one of the lead singers.

But watch any show like "The Voice" and you often see someone pull them out, which happens for a couple of reasons. For example, when their ears are sealed off it's hard to hear anything else. At other times there might be a problem with the mix they're hearing.

"You can get all messed up," Scott points out.

But apparently a lot of times it's just to allow the performers to feel the moment.

"I think a lot of it is wanting to feel the audience because there is a little bit of that, that happens whenever you seal your ears with these ear monitors so being able to feel the crowd and hear the applause for sure," Scott adds.

And with the release of their new song compass Lady Antebellum is hearing a lot of applause.