Educational materials called "hearing-training equipment" have drawn considerable interest in the recent years, with one product named best selling item on one of the major Internet shopping sites. They are usually used to improve English listening skills, and their popularity indicates that they are widely believed to be helpful, at least to some extent, in achieving that goal. In other words, customers purchase these products with wishful thoughts that they might finally be able to acquire the listening and speaking skills in English. On the other side of the coin is the fact that we, the Japanese, are still struggling to learn these longed-for skills. In fact, although the "international society" has long been our mantra, our English skills are still far below the level required in international situations. However, the field of English education does seem to have made some progress, i.e. from the conventional method of repetitive listening to a new, more systematic one that these products claim to offer. On the other hand, the field of vocal music has seen little progress in the past decades. It is true that many of music college graduates now go abroad to study in "music capitals" of the world. The overall level has risen, with increasing number of Japanese becoming world-class singers. However, when it comes to teaching, the conventional method of simply having students imitate teachers' voice is still prevalent. With such situation in the background, this paper examines the effect of the hearing-training equipment and explores possibility of applying this method to vocal music education by analyzing difference in the way the Japanese and westerners perceive sound they hear.