I've be PMing one of the DN reps on here about options to upgrade to a HD system. We have two TV's, one is HD capable and one is not. Currently, we have a 625 dual tuner hooked up in the basement to our SDTV and then coax run upstairs to our HDTV. DN is proposing a HDTV dual tuner (they didn't say which model). My question is, if it's installed in our basement like the current 625, how can I hookup the receiver so I can use the surround sound in the basement, but get the good HD signal upstairs?