FM77

You will need to increase the STC (Sound Transmission Class) of your windows to over 40 to block most sound frequency above 125Hz to the high freq range, a single pain has poor STCbelow than 20, double pane has STC close to 29-32, a 10 STC unit increase is about 50% reduction in decibles. Check out the windows at www.milgard.com, this might be what you need. Also doing a double sheetrock with Green Glue in between will hel to dampens the low frequency being transmitted through the wall structure, although the weak link is the windows and doors.