To see if multi-channel electrical stimulation could reproduce speech, Clark led the development of a cochlear implant providing multi-channel stimulation, and receiving operating instructions by radio signals through the intact skin (top). This enabled different theories on how to code speech with electrical stimulation to be tested. The University of Melbourne’s prototype was implanted by Clark as the senior surgeon on 1st August 1978 (centre). The free-fitting banded array with graded stiffness passed around the cochlea to lie opposite the nerves transmitting the speech frequencies to the brain on a place coding basis. The patient, Rod Saunders, made a relatively uneventful recovery and participated in studies to determine what the electrical signals sounded like and how to develop a speech code that could be understood (bottom).