You can control for that with casting. I don't think it was until Ira Glass came around that we got away from it in radio. Looking back even further, consider

You can control for that with casting. I don't think it was until Ira Glass came around that we got away from it in radio. Looking back even further, consider the influence of the electric microphone on music. It used to be that you had to be able to project to the entire room with your own power, but now many quieter varieties of voices are able to compete too.