I believe a once long time member here did some tests, and the most noise isn't from the track but from the layout top vibrating like a drum. He found hanging heavy curtains on the edge of the layout not only hid everything under the layout, but also went a great ways to reducing the noise.
My layout is Atlas track on Midwest cork wood glued to felt 3M spray adhesived to Home Depot Quiet Brace liquid nailed to 1/2 plywood screwed to an overly build framework. I use Atlas track screws to hold the track down, they do not go into the plywood. The layout is attached to the wall on one of the short ends. Is it as quiet as I want, nope. But it is as quiet as I'm going to get it. I've done what I can and I'm going to move forward and enjoy it as I build and run. The return on investment to make it quieter is not worth it, so I won't worry about it anymore. Good luck and have fun!
