rb is correct, they feel different to people even when they experience the same thing.
I can feel them at home in Alaska when they are around 3.0, usually hear it before I feel it. One day thought a car had slammed into the house.
But I felt a 4.4 when I lived in San Diego and to me it was about the same as the smaller one in Alaska.
Part of the year I spend in Nevada, I never feel them even though they are usually close to me.