Nothing will spawn within a certain range of a workbench. Build a wall away from your compound some distance, all the way around. Put workbenches along the wall on the inside, far enough apart so you can repair the wall everywhere. This prevents random spawns close to your base. This will keep them from spawning close enough to hear or see you or your base, so you wont be bothered again unless you are doing something out by the wall, like cutting trees or breaking rocks..

This does not prevent special event attacks. Skeleton surprise, smell from the swamp, etc.

edit: Spawns can see fires and torches from a long way away. This will draw them for quite some distance.