Voice Quality: Functions, Analysis and Synthesis
August 27-29, 2003
A large percentage of patients who have undergone laryngectomy to treat advanced laryngeal cancer rely on an electrolarynx (EL) to verbally communicate. While serviceable, EL speech is plagued by shortcomings in both quality and intelligibility. As part of a larger ongoing effort to improve the oral communication of EL users, this study has attempted to better quantify the sources and perceptual impact of abnormal acoustic properties typically found in EL speech. EL speech tokens that were enhanced using combinations of three different improvements, low frequency enhancement, self-noise reduction, and added pitch information were presented in pairs to a group of ten listeners. Listeners were asked to judge which of the two tokens sounded most like normal natural speech and then to rate on a visual analog scale how different the chosen token was from normal speech. The results indicate that although EL speech can be most improved by removing its self-noise and providing proper pitch information, the resulting quality is still well below that of normal natural speech or even that of monotonous natural speech. This suggests that in order to effectively improve the quality of EL speech, other attributes that contribute to its unnatural quality must be explored and corrected.
Full Paper Presentation (PDF) Presentation (Powerpoint; 1510 KB)
Bibliographic reference. Meltzner, Geoffrey S. / Hillman, Robert E. (2003): "Impact of abnormal acoustic properties on the perceived quality of electrolaryngeal speech", In VOQUAL'03, 73-78.