Effect of Duration upon the Intelligibility of Synthetic Vowels
Ronald W. Wendahl, Agnes Lashlee Case, Richard W. Stream · The Journal of the Acoustical Society of America · 1960
A series-resonant synthesizer was used to tape-record ten vowels, replicated once at five durations ranging from 80 msec to 1.3 sec. Growth and decay, inflection rate, fundamental frequency, and intensity were held constant. The recorded stimuli were presented to 16 judges who transcribed them in phonetic script. The results indicate the importance of duration of synthesized vowels upon intelligibility and indicate optimal values for programming a synthesizer. Also, it was found that vowel duration is a less significant factor in determining the intelligibility of synthetic vowels than it is for the human speech mechanism.