1. Ear The Organ of Hearing and Balance Sound waves enter the ear through the auditory canal and then travel through the eardrum, where they are Converted to vibrations. Millions of Tiny hairs in the inner ear's cochlea Convert the vibrations into electrical Nerve signals, which are sent to the brain through the Eustachian tube for Processing. 3 1 2 4 Auditory canal Eardrum Cochise Eustachian tube Bill Tracy : CATALUÑA,JENNIFER C .