Sound amplifiers have wide variety of shapes because of its high degree of freedom of shape. However, many existing products of sound amplifier focus on material and appearance. There are few things that emphasize the functionality of the shape conveying sound. There is the study to raise the radiation efficiency of sound by devising the shape of the acoustic horn. There are many studies of such communication aids. However, there are few studies on sound amplifier. So I clarified the influence on the sound by the shape of sound amplifier. Thus we set the acoustic measurement experiment of the sound amplifier based on the acoustic measurement of the speaker. Then we conducted experiments on 12 paper mocks and 15, 3D printer models. As the result, We were able to get tendencies of acoustic characteristics in sound amplifier. We think that this knowledge can be used for speaker design.