Well there are many ways to pronounce "HNNNNNNNGGGGGGGGG."
You can do it through your nose, with a deep sound, with a high sound. If you want you can make your voice crack while doing it. That one is a favorite. When you take a shit and you do it the bathroom there is an echo. (If its tile.) While on the bus and you do it you can hear the humm of the engine and sometimes people will stare.
There are just so many ways to pronounce "HNNNNNNNGGGGGGGGG."