Creaky voice refers to 'a vocal effect produced by a very slow vibration of only one end of the vocal cords' (Crystal 1997, 98). Previous creaky voice researchers agree that the creak voice often occurs at voice pitch levels below those of the modal register (Hollien et al. 1966).
Examination of natural conversations held by relatively young middle class Japanese and American men and women revealed that females utilize creaky voice more than males. Female speakers of standard varieties of American English employed creaky voice more frequently than American males, Japanese males and Japanese females. The frequency of creaky voice usage by Japanese, females while conversing with a familiar interlocutor were similar in frequency to that of their male counterparts. However, usage of the creaky voice by Japanese females increased noticeably when conversing with unfamiliar as opposed to familiar interlocutors.
Preliminary perception test results indicate that listeners of these cultures correlate creaky voice by female speakers with differing images. American listeners (regardless of gender) appear to associate this voice quality with knowledgeableness and pretentiousness while Japanese listeners (regardless of gender) seem to identify it with formality and hesitancy.
For this group of American women, the creaky voice may operate as both an assimilator of low-pitched male voice often accompanied by this voice quality and as the projector of an image of contemporary professional women. Relatively young and educated American women may unconsciously utilize this voice quality in their aspiration to appear competent and knowledgeable.
Japanese female speakers, however, possibly resort to creaky voice usage in order to achieve the desired cultural style of parlance as it especially helps to increase the occurrence of low-pitched voice, contributing to emphasizing the unemotional restrained speech style necessary for situations where individuals interact with those unfamiliar in Japanese culture.