The Impact of Nasalance on Cepstral Peak Prominence and Harmonics‐to‐Noise Ratio

Abstract

Objectives/Hypothesis Cepstral peak prominence (CPP) has been reported as a reliable measure of dysphonia and a preferred alternative to harmonics‐to‐noise ratio (HNR). However, CPP has been observed to be sensitive to articulatory variation and vocal intensity. The aim of this study was to examine the impact of nasalance on CPP and HNR of voice signals. It was hypothesized that increased nasalance would be associated with decreased CPP. Study Design Within‐subject correlation design. Methods Thirty vocally healthy female participants were recorded reading and producing a vowel in alternation with a nasal consonant while wearing a nasometer for calculation of nasalance. Recorded vowel, nasalized, and nasal segments of speech were used to calculate CPP using Analysis of Dysphonia in Speech and Voice software, and HNR and vocal intensity using Praat software. Results Significant main effects of conditions were observed for CPP. CPP values decreased significantly when phonation changed from vowel to nasalized vowel and to nasal. There was correlation between CPP and nasalance and between CPP and intensity. HNR was slightly higher in the nasal condition than in vowel. There was a weak correlation between HNR and nasalance. No correlation was found between HNR and intensity. Conclusions CPP is sensitive to changes in vocal tract configuration caused by nasalization as well as intensity, whereas HNR is not. Therefore, CPP may reflect the periodicity in source signal or the filtering effects of vocal tract. Further research is needed to clarify the application and interpretation of CPP in clinical practice. Level of Evidence 4 Laryngoscope, 129:E299–E304, 2019

Acoustic voice characteristics with and without wearing a facemask

“…In addition, why HNR was higher in mask-wearing conditions whilst CPPS remained unchanged was unclear. Although HNR and CPPS actually reflect different phenomena in voice quality 49 , the non-significant changes in CPPS and vocal intensity across conditions did not appear to support www.nature.com/scientificreports/ the compensation assumption. In addition, phonation compensation in mask wearing may include increased vocal effort, as reported in a previous study 13 .…”

“…It has been considered a significant predictor of dysphonic severity 46 . However, there are inherent limitations of cepstral analysis, that is, it is affected by vowel types and vocal intensity 47 , vocal tasks 48 , vocal tract 49 , and the algorithm of software packages 48 , 50 . Vocal audibility can be examined both by spectral energy at different frequency bands and sound intensity, which can also be estimated from the acoustic signals.…”

Impact of Instructed Laryngeal Manipulation on Acoustic Measures of Voice–Preliminary Results

“…Instead, it reflects the fact that the cepstral measurement was highly dependent upon vocal tract effects, as suggested in previous research. 55 Alternatively, the mechanical coupling effect described by Fink and Dumarest 6 and Iwarsson and Sundberg 34 would result in a reduced CQ at a lower larynx due to the abductory forces on the arytenoids when the larynx is pulled caudally by either sternothyroid and/or accessory extrinsic muscles ( Figure 5). A reduced CQ produces less spectral energy in the vocal signal, which would result in a lower CPP value.…”

“…53 It is however also influenced by intensity 54 and nasal resonance. 55 Although a physiological link between differential laryngeal manipulation and the above-mentioned acoustic measures particularly HNR and CPP has not been established experimentally, it is useful to use those measures to explore how the voice changes as a result of laryngeal manipulation in vocally healthy speakers as these are common acoustic voice outcome measures. This study aimed to examine the immediate effects of manipulating FVFA, TVFM, and LH on frequency-and spectral-based acoustic voice measures.…”

The Power Cepstrum Calculation with Convolutional Neural Networks

“…The ratio between the peak magnitude and the rest of the cepstrum is used to determine certain features of vocal quality. This ratio also allows the classification of voices according to their level of noise, breathiness and nasality [7,8]. On the other hand, the mel frequency cepstral coefficients (MFCC) are very useful for speech recognition [1].…”