CPPS and Voice-Source Parameters: Objective Analysis of the Singing Voice
Calvin Peter Baker, Johan Sundberg, Suzanne C. Purdy, Te Oti Rakena, Sylvia H. de S. Leão
Abstract
INTRODUCTION: In recent years cepstral analysis and specific cepstrum-based measures such as smoothed cepstral peak prominence (CPPS) has become increasingly researched and utilized in attempts to determine the extent of overall dysphonia in voice signals. Yet, few studies have extensively examined how specific voice-source parameters affect CPPS values. OBJECTIVE: ), vibrato extent, source-spectrum tilt, and the amplitude of the voice-source fundamental on CPPS values. MATERIALS AND METHODS: A series of scales were synthesised using the freeware Madde. Fundamental frequency, vibrato extent, source-spectrum tilt, and the amplitude of the voice-source fundamental were systematically and independently varied. The tones were analysed in PRAAT, and statistical analyses were conducted in SPSS. RESULTS: and source-spectrum tilt, independently. A nonlinear association was seen between vibrato extent and CPPS, where CPPS values increased from 0 to 0.6 semitones (ST), then rapidly decreased approaching 1.0 ST. No relationship was seen between the amplitude of the voice-source fundamental and CPPS. CONCLUSION: should be taken into account when analyzing the voice, particularly in singing-voice research, when comparing pre and posttreatment data, and when comparing inter-subject CPPS data.