relax sound! Natural sounds in Japan for relaxation

Can't you relax, sleep well, concentrate on your work?
You can enjoy 4 effects, "inducing sleep", "relaxation", "having a good memory", and"concentration", for free!

The key of those good effects is listening comfortable sounds and binaural beats at the same time. Binaural beats make your brainwave good state, and comfortable environmental sounds make you relax.