I set my anvil on a sandbox, and that seems to me to be quieter than a stump, which is more rigid and doesn't dampen the anvil's vibrations as much. Other advantages of a sandbox are that the anvil on sand doesn't move around much when you hit it, so I don't have to fasten mine down, and it's easy to make fine adjustments on the height--just add or remove some sand as needed. The downsides are that a large box of sand like that will be HEAVY, so you would probably want to find a good spot and leave it there, and if it's outside, you'll need to keep it covered to keep the weather out. I screw down a piece of plywood over the top of mine when I'm not using it.