Loops

Loops have not yet been added to the game, but have said to be played when the player is in a specific condition (In caves, woods, sea and beside a waterfall)

They can be found in /.minecraft/resources/sound/loops/, they can be converted to reveal loops of birds chirping, cave chimes and waterfall noises.

Converted
Converted files can be downloaded by clicking on the following links:

Birds Screaming Loop

Cave Chimes

Ocean

Waterfall