Mike Gretchen
Now you see why some of us loved polybutylene (the non defective stuff with brass and copper fittings and copper rings) for many low chlorine situations. It was quiet and also got rid of water hammer. Copper tends to allow the sounds to travel. One way to have less sound DURING construction is to OVER size the piping. That way the water travels at a slower (and quieter) rate. Isolating the copper from all points of contact with felt, rubber or plastic straps will help somewhat as well.
