Need help quieting noisy window

Hey guys.. I've got a window in our bedroom that seems to let in LOTS of noise from our neighbor's house. It usually isn't a problem unless their dogs are barking and then it sounds like the ^*(% dogs are in our room. Last night the parents went out of town and the kids were a bit ruckus on the patio and we were awoken a few times. So that's the backstory.

The windows are single-pane double-hung windows if I'm correct. It's basically two separate windows hung back-to-back with a 1/2" to 3/4" gap between them. What can be done to dampen the sound?

Your help is greatly appreciated by both me and my wife!!

 

You may be able to attain some quieting by just changing the window to a replacement double pane, single hung window, unless you regularly lower the top half, and most people don't. It isn't difficult to do as a diy project.

 

That is an easy project? Hmm.. I would have thought it'd be pretty difficult. I'll have to do some searching to see if I can find the procedure.. Thanks!