In Thomatis Method, which is based on the principle that one can reproduce only those sounds that one can discern, vocalization training for a singer starts with a hearing test. According to the test results, each singer is assigned a personalized training program, in which some lessons for refining the singer's auditory sense are given, using equipment called oreille electronique, before lessons aimed at improvement of vocalization itself. In other words, the method seeks to improve vocalization by way of improving hearing abilities. This study tries a variation of this method, by omitting the first part of the process and starting directly with singing lessons using the oreille electronique. Subjects of the experiment are Japanese students majoring in vocal music. They are given regular lessons for a certain period of time, and the outcomes of the lessons are measured by changes in perceived tones of sounds that the students hear or produce. The oreille electronique that the students use during the lessons is tuned for Italian, which is one of the most commonly used languages in the field of vocal music. How students perceive the tones of received or produced sounds of five di?erent languages, i.e. Japanese, English, Russian, Italian and American, is tested before and after the lessons in order to see if there is any change. Analyses are also made on the relation between the perception of received sounds and that of produced sounds. The test in the Italian language is repeated after one week to examine the extent of retention of any change that may have occurred.