I’ve got one on the front door, and a different one on the back door. The front on is a traditional chime, and the rear is an electronic unit. I would say the rear has higher frequencies in it, but I mainly think it’s the sudden loud(ish) noise that is the key as they generally make me jump as well, especially the front one.
Cheese and (Tomato) ketchup sandwiches are good, I’ve had a few in my time :-)