We live in an old (110 yr+) farmhouse. We also live 3500 feet from a granite quarry and are assaulted by the noise from the jaw crusher and hydraulic hammer from dawn to dusk every day. Even though they are in noncompliance re: county's SUP, it doesn't matter. The quarry does what it wants without oversight. County looks the other way. We're considering adding insulation to the walls -- would that make much of an effective sound barrier? Even minimizing it some might save our sanity (I think after so many years of the roar and pounding, our sanity is already gone). It's mainly the low frequency that we have to deal with but it isn't background noise. It's in your face. Any suggestions would be helpful (and don't think we haven't thought about moving but we love our farm).