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The aim of this study is to synthesize pathological breathy voice and to make a cepstral peak prominence (CPP) tablefollowing breathiness ranks by cepstral analysis to supplement reliability of the perceptual auditory judgment task. KlattGridsynthesizer included in Praat was used. Synthesis parameters consist of two groups, i.e., constants and variables. Constantparameters are pitch, amplitude, flutter, open phase, oral formant and bandwidth. Variable parameters are breathiness (BR),aspiration amplitude (AH), and spectral tilt (TL). Five hundred sixty samples of synthetic breathy vowel /a/ for male werecreated. Three raters participated in ranking of the breathiness. 217 were proved to be inadequate samples from perceptualjudgment and cepstral analysis. Finally, 343 samples were selected. These CPP values and other related parameters fromcepstral analysis are classified under four breathiness ranks (B0~B3). The mean and standard deviation of CPP is 16.10±1.15dB(B0), 13.68±1.34 dB(B1), 10.97±1.41 dB(B2), and 3.03±4.07 dB(B3). The value of CPP decreases toward the severe groupof breathiness because there is a lot of noise and a small quantity of harmonics.
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