Making English Voices Similar to the User’s Voice by Using Interactive Differential Evolution

Abstract

English skills are becoming necessary for students who would like to give a presentation at international conferences. However, it is very difficult for non-native English speakers to speak in English because of the differences between English and their native languages. There are some ways to practice speaking English such as Shadowing, and if the audio is similar to the learner's voices inside their heads, it should be more comfortable for the learners to listen to it and repeat after the audio. We propose a method to make English voices similar to the user's voice by using Interactive Differential Evolution. Experiments were conducted with the concrete system of IDE. 9 examinees participated in the experiments through 10 generations with 6 vectors in each generation and kept choosing the better option. After the experiment, we randomly chose 2 voices from the initial and final generation and asked the examinees to evaluate them. As a result, significantly higher evaluations were obtained in the voices from the final generation.