The Problem with head phones and ear buds, is it’s very difficult if not impossible (with headphones) to listen to a Hemispheric Brain Synchronization audio recording (or any audio recording for that matter) while laying on your side.
Headphones are fine if you are sitting up or laying flat on your back
Ear Buds are just about the same. They are fine if you are in any position except laying on your side!
The March 2007 issue of “Wired” had a review of Ear Buds on page 102 and had this comment about the $400.00 Ultimate Ears triple fi 10 Pro, “...if you nod off, keep you head straight or you might pierce an eardrum.”