A Hawk or Owl maybe?

Let me apologize in advance, I know nothing about birds.  However, recently we've been hearing these  calls or screeching sounds early evening to late at night.  It's a new sound that we've haven't heard before and it seems to be communicating with another bird in the distance with the same call.  

It usually starts around 5pmish until late at night...so I thought maybe they were owls.  I could be way off base but some help would be truly appreciated.  I think all of my family members have gone out looking into the trees trying to find these birds that we can't seem to locate. It would be nice to put a picture to them.  We are located in the Mid-Atlantic if that helps anyone...

I've recorded the birds with my iphone from within my house (yes they are that loud). 

Soundcloud of birds (Starts 4secs in and you may have to turn the sound up...)