 Voice actor Nicholas Briggs adopted a different voice for each model : he adopted a grandiose voice for the Supreme Dalek to fit his perception of the character as egotistical ; and he adopted a sing @-@ song voice for Caan to reflect the character 's insanity as a result of entering the Time War . Briggs justified his interpretation of Caan by explaining that " [ Caan ] can 't tell when he 's happy or sad , his emphasis is very strange and he finds things funny when things aren 't funny " , creating a soothsayer personality with an " almost pure " mind . An expanded theory was published in Briggs ' interview with Doctor Who Magazine in July 2008 : 
