Go to this website to play many videos at once. AudioGravity
There are about 18 different videos you can play together to create your own blenfd of music. This is a good example of how the components mix together to become one single larger sound.
This is more information from the web site...
The videos can be played simultaneously -- the soundtracks will work together, and the mix can be adjusted with the individual volume sliders.
Learn more in the FAQ.