Reply to "Sound deadening materials"

I have good results with plywood, foam board, and topped with ceiling tile using Fastrack. Don't know what is meant by running at scale speeds, as 60 smph sure is a lot louder than 20 smph. I run trains at 20 smph, and my db app reads 65 or 66, which is normal conversation. At 40 smph it reads high 70s, which is heavy traffic. I like to run slower because there is less repetition.