Thread: how loud ?

I know the "directions" on some mp3 files state that you should have it only loud enough so that you can make out what is being said (if there are words spoken) but not so loud that it will keep you awake.

The key is does it state that it's ok to fall asleep or does it state that all benefit will be lost if you do? If you don't know the answer to that question.. ask the person/company that created the mp3 file.
.

thanks