Voice Pitch Control Using a Two-Dimensional Tactile Display

It is difficult for the deafblind, or the hearing impaired, to control the pitch of their voice because they cannot perceive it. In particular, when singing, it is very difficult for them to control the pitch of their voice because they need to maintain a stable tone. We have developed a voice pitch control system to assist their singing by means of a tactile display. Using this tactile feedback system, we verified in a previous study that two deafblind subjects were able to control the pitch of their voices with as much accuracy as hearing children. By using this tactile feedback system, the correspondence between musical scale and proprioceptive sensation (muscular sensation, and so on) of the two subjects was returned to pre-hearing loss levels. They sung using not only tactile feedback but also proprioceptive feedback. In this paper, we investigate the ability of hearing subjects to control the pitch of their voice using our tactile feedback system, but without auditory feedback. Seven hearing participants were examined under two conditions—“without tactile feedback” and “with tactile feedback”—to ascertain their abilities to control their pitch while subjected to a masking noise. The results indicated that hearing subjects could not sing with an accurate pitch using only the proprioceptive feedback (“without tactile feedback” condition).