Incipient tonogenesis in Phnom Penh Khmer: Acoustic and perceptual studies

Unlike many languages of Southeast Asia, Khmer (Cambodian) is not a tone language. However, in the colloquial speech of the capital Phnom Penh, /r/ is lost in onsets, reportedly supplanted by a range of other acoustic cues such as aspiration, a fallingor low-rising f0 contour, breathy voice quality, and in some cases diphthongization, e.g. /krA:/ ‘poor’ > [kÒA], [khǑA], [kO ̈ A ̈ ], /kru:/ ‘teacher’ > [kù:], [khǔ:], [ku ̈ :]. This paper presents the results of production and perception studies designed to shed light on this unusual sound change. Acoustic evidence shows that colloquial /CrV/ forms differ from reading pronunciation forms in terms of VOT, f0, and spectral balance measures, while a pair of perceptual studies demonstrate that f0 is a sufficient cue for listeners to distinguish underlying /CrV/-initial from /CV/-initial forms, but that F1 is not. I suggest that this sound change may have arisen via the perceptual reanalysis of changes in spectral balance, coupled with the coarticulatory influence of the dorsal gesture for /r/.