On the point of Routh, it was mainly the script. However, his voice was perfect for Clark Kent but too high for Superman. He should have spoken lower. Reeve Had both voices perfect; a slightly deeper hero voice versus a slightly quirky, higher voice. Cavill only really had to do the Superman voice. His Superman voice was fine for the most part but it became too casual at times. His Clark Kent voice was far too deep, hopefully he'll fix that since he also seemed to confident.