I have found a good link that explains what Diegetic and Non-Diegetic sound is and it also has some examples of the different types of sound.
Diegetic sound:
This is where you can hear a sound and at the same time you can also see the action of the object or person that is creating the sound.
- actors speaking to each other (dialogue)
- sounds originating from any object on the screen, like footsteps and police sirens
- music that comes from a sound system or orchestra
Non-Diegetic sound:
Sound is said to be nondiegetic when its source is not present or implied in the narrative universe. Common instances are:
- music or score, used to augment emotions
- actor’s commentary or narration
- any extra sound added for effect
Non-diegetic is also known as commentary or nonliteral sound.
https://paulolohan.wordpress.com/2013/05/21/the-difference-between-diegetic-and-non-diegetic-sounds/On this link page it shows how a film called Zombieland sounds different it the non-diegetic sounds have been taken out and from what i can tell is that most of the noises in this film are actually non-diegetic because when they play the clip again it sounds so much different and the sounds are not as loud and they don't really sound the same as they do on the actual film with the non-diegetic sounds in it. They have used a number of different non-diegetic sounds such as:
- Walking
- The gun reloading
- When they gulled the guns out
- When they opened the van back doors
https://www.youtube.com/watch?v=YreJ0SamM0I
In this film clip they have used both diegetic and non-diegetic sound such as:
Diegetic:
- when they are talking
- When they get into the barrels and fall into the water
- When the hatch opens and closes
Non-Diegetic:
- The walking on the wooden floor
- The music in the background
