Adds a nice, strange atmosphere.
It's nothing for stock like maps though 
People don't take much notice these days of the round changing sounds other than notification that a round has ended or starting.
When it's a non-stock round sound playing it creates quite a nice change, makes it feel different and to be honest I'm glad now this has started happening since nothing on it has been done much since the game was out.
Ray's probably the first as I can see in taking the first step to custom round sounds that aren't commonly heard in Black Ops 2 which is great, I love seeing people being creative and coming up with fresh new idea's and I can only hope we'll soon have a nice variety to choose from.
So, Thanks to Ray for those and hope you guys enjoy using these.
DuaLVII