Interactive Evolutionary Computation (IEC) is well known as an effective method to create media contents suited to user's preference and objectives to use. As one of the methods, we have applied Differential Evolution, which is recent evolutionary algorithm to IEC. Concretely, we have already presented a method that creates sign sounds with Interactive Differential Evolution (IDE). This study aims to investigate fundamentally the efficacy of the IDE method in comparison with Interactive Genetic Algorithm (IGA). Two listening experiments were conducted: experiment 1 as a creation experiment with IDE and IGA, experiment 2 as a re-evaluation experiment. Target of the creation was warning sign sounds. In the experiment 2, representative five sign sounds created in both of IDE and IGA were evaluated. Sixteen males participated as subjects in the experiments. In the result of the experiment 1, IDE overcame IGA in subjective fitness value. Drastic shrink of searching space was observed in IGA, and larger time cost was observed in IDE. In the result of the experiment 2, higher fitness value in average was observed in IDE, however, the difference was not significant.