PHONETICS LABORATORY In the phonetics laboratory, various types of machines and instruments are employed in the study of sound materials collected in field studies. In order to record and examine the characteristics of the sounds and the articulation of speech sounds, the following machines for analyses are available: a sound-spectrograph, a pitch extractor and an electro-palatograph. The sound-spectrograph attached to a computer makes frequency analyses of sound waves, extracts components of the sound wave at a certain time, and shows them as a particular pattern in black and gray colors on the screen. The pattern can be printed out on a special paper. The pattern may be obtained either on wide-band or narrow-band. The wide-band pattern mainly shows the length and quality of each sound wave, while the narrow-band one shows the height of the fundamental frequency and its height change, as well as its length. Furthermore, this machine includes functions of FFT analysis as a certain time (i.e., section analysis), LPC analysis (to estimate of the vocal tract transfer function) and so forth. The maximum recording time is about ten minutes (at 20KHz sampling) on the present computer system and the machines can analyze long time data like sentences. Furthermore, a part of the recorded sound wave can be deleted or a part of a different sound wave can be appended at any point of the originally recorded sound wave, and a new sound wave can be created with this machine. A new Digital Sound Spectrograph has been recently acquired by the Information Resources Center of the Institute. This new machine has real-time capability. The pitch extractor analyzes the fundamental frequency and the degree of sound strength, and displays the result on the screen. This machine can select frequency ranges for input sounds (e.g., male, female and child sounds) and it enables us to obtain much more exact data on fundamental frequency than can be obtained by using the sound-spectrograph. The electro-palatograph is one of the devices for observing directly and recording the articulatory movements of the tongue. The artificial palate, which is embedded with 32 small electrodes, is attached to the speaker's hard palate. The 332 small lamps on the front surface of the machine indicate, by going on and off, how the tongue contacts with the electrodes at each point of time. The result is recorded on special paper. In addition, there are tape duplicators for copying tapes and a video tape editor. There are also various types of tape recorders and a sound-proof room for exact recording. The speech and language library attached to the phonetics laboratory holds important recorded materials on languages, folk tales and folk music obtained through field studies. Recorded disks and tapes of various languages in the world are available for loan.20
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