Experimental verification of a new theory of acoustic signal detection in the inner ear related to noncontact detection of potential changes on the tectorial membrane

•A novel theory of acoustic signal detection in the inner ear.•The acoustic frequency that cuts our brain out of the audible band.•Unheard acoustic frequency bands in 3.5 kHz ÷ 4.4 kHz range.•The existence of the natural frequency of stereocilia.