Abstract
Sound pressure in the nasal cavity during phonation of speech sounds was measured by a probe tube microphone in eight normal adults (four males and four females). Simultaneously, the sounds in the nasal cavity were recorded by a tape-recorder and analysed by a Sonagraph. The measurements of the sound pressure was made about sixty-seven japanese monosyllable speech sounds. The results are as follows:
(1) The sound pressure in the nasal cavity differs in compliance with individuals; generally, in the individuals with soft and beautiful voice the sound pressure is larger.
(2) Difference of the sound pressure in the nasal cavity are observed also in compliance with vowels and consonants.
(3) In vowels, generally, an order as follow is observed;
I>U>E>A, O in each individual, however, some different orders are revealed.
(4) Concerning consonants, the sound pressures of nasal-syllables are extremely larger than the others. In the others, vowel-, glide-, voicedconsonant- and [h]-syllables reveals larger sound pressures than voicelessconsonant-syllables.
(5) In nasal consonant waves and preceding waves of the voicedconsonant-syllables, a marked rise of sound pressure in the nasal cavity is observed compared with at the front of the mouth.
