The use of sampled consonants for improved intelligibility in formant synthesizers

This paper investigates the improvement of intelligibility in a formant synthesizer by using a library of sampled consonants extracted from natural waveforms. Four hundred and seventy‐one monosyllable words containing consonants in all possible vowel environments from a male American English speaker were recorded. The current focus is on the voiceless consonants. A comparison test was conducted between our current synthesizer [K. Matsui et al., Proc. ICASSP 2, 769–772 (1991)] and the sampled consonant system. Eight naive listeners participated in a simple intelligibility test. The stimuli list consisted of 110 tokens, 60% of which were nonsense words. The results showed that the sampled consonant system was significantly higher (by 20%) in overall intelligibility score. In terms of consonant classes, initial stops showed the most improvement with a 26% increase. Weak fricatives did not show a dramatic difference between the two systems. In further experiments these were improved utilizing additional facto...