Acceptable operating force for buttons on in-ear type headphones

The touch headphones are a solution for providing playback and volume controls on in-ear type headphones. One of the issues with placing controls on earpieces is that applied pressure is transferred to the inner ear, which potentially creates discomfort. The experiment described in this short paper shows that conventional button switches are not well accepted. Users preferred to operate a button on an earpiece with a force of around 85 grams.