“…In a series of psychoacoustic experiments using similar acoustic patterns, the results for DEMOSTHe´NES ranged from 94.5% to 96.47% correct responses for sighted users and users with visual impairments, respectively, in single word tasks; and from 97.5% to 98.1% correct responses for sighted users and users with visual impairments, respectively, in single sentence tasks (Argyropoulos, Papadopoulos, Kouroupetroglou, Xydas, & Katsoulis, 2007). These results are comparable to results for the DECtalk for two reasons: (a) substantial data exist on the intelligibility of the DECtalk TTS system (von Berg, Panorska, Uken, & Qeadan, 2009), and (b) DECtalk is one of the most widely used TTS speech synthesizers in the AAC field (Koul & Hester, 2006;von Berg et al, 2009).…”