Raw by Kevin MacLeod
This low bass guitar piece is dirty and raw; the strings are forcefully played, and you can hear the vibrations, the squeaks, and the ruggedness, all of which creates a carefree attitude. The drums are barely noticeable. The other bass accompanies the root bass without ever gaining prominence. When the drums stop and the bass plays its final refrain, you can really hear how the music is refreshingly unrefined.
This piece of music is available in an uncompressed format here.