Speech cue enhancement in intervocalic stops

Abstract

The place of articulation feature for stop consonants is subject to many errors in speech processing by hearing-impaired listeners. Attempts to improve the recognition of initial and final stop consonants by lowering the level of the first formant or—with a different approach—by narrowing the formant bandwidth of the first five formants only very partially led to satisfactory results. Intervocalic stops were used in the present investigation, on the one hand because the spectral information is represented twice (in the VC as well as in the CV-transition) and, on the other hand, because the closure duration offers additional information to the listener. The modification of bandwidth led to no noticeable improvement in the /b, d, g/ discrimination. A change of the closure durations affected the identification of the stops, especially the /b/. The modification of the transitions of the second and third formants optimized the recognition rates for /b/ and /g/.