The effectiveness of the Speech Enhancer[TM] (SE) on single-word, sentence, and spontaneous speech intelligibility was investigated for a single female speaker with hyperkinetic dysarthria resulting from cerebral palsy. Data were taken with the SE worn with a headworn voice amplifier (the Voicette) and in an unaided control condition to enable comparisons of % intelligibility scores in each condition. Percentage intelligibility results were taken via transcription of audiotaped data by a range of experienced and naive judges who were blind to the device used. Results indicated that the SE was effective in improving intelligibility for one experienced judge, but the degree of improvement in intelligibility varied between judges and speaking conditions. Results are therefore inconclusive that the SE increases intelligibility, especially with naive listeners where the unaided condition produced highest intelligibility scores. Clinical implications are discussed.