You don't even have to be looking at the screen to know an episode of the "Law & Order" franchise has just started or transitioned to a new scene. All you have to do is hear the iconic sound: dun-dun.

Dun, dun or chung, chung? Call it what you will. We can all hear that iconic “Law & Order” opening sound effect — which carries through each and every episode on scene changes and has into various ...