Diegetic and Non-Diegetic Sound in Music Videos

Diegetic sound is any sound presented as originated from a source within a film's world - eg speech.

Non-Diegetic sound is sound that the viewer can hear but the characters/performers on screen are not aware of as it is not 'in-universe'.

All music videos use non-diegetic sound - the music. Some, however, use diegetic sound as well. Generally, if diegetic sound is found in a music video it plays a part in some kind of narrative.

Here is an example of a music video which uses non-diegetic sound:

Bon Jovi - It's My Life

In this video, as with many other music videos, the diegetic sound is used for narrative purposes. The sound includes speech, computer/phone sound effects and the sound of a lorry skidding out of control. The video is a mixture of narrative and performance. The sound is used only in the narrative sections of the video, while the performance is exclusively the music.