Every wondered what would you happen to a sad song if you changed the beat? Or what would happen if you took a song like "Happy" from Pharrell Williams and slowed it down? Well, you'll be happy to know you weren't alone.

A group on YouTube, The Gregory Brothers have taken some popular songs and experimented with them to see if by changing the key of the song, it can change "the mood' of the song as well.

You can check out their experiment in the video above.