Thanks mark for your good explanation. So that means that standing near a mower for a few seconds is much more a problem than billard balls hitting together? Then why does one usually not feel the lonlasting sound compared to the short ones? I noticed that the billard balls can cause a bit of pain inside the ear(not necessarily the brain) when they hit very hard. I never experienced something like that with a mower.

Well I would say that I am overall very sound sensitive. The idea with the ear plugs was the next thing I wasvplanning to do.