Purebuds Earphones claims that their use of "Reverse Sound Technology" makes their earbuds safer, preventing hearing damage. I searched for a scientific study of this technology, or at least a good explanation of it, but couldn't find much.
From what I can understand, the speaker in the earbud is pointed away from the ear, so the sound isn't emitted directly into the ear canal.
From reading reviews of the earbuds, they are actually quite loud and the bass is just as prominent if not more so.
Has Purebuds' claim that their earbuds are safer ever been scientifically tested?