Objective:
The Nasal Resistance (NR) Technique is a semi-occluded vocal tract exercise (SOVTE) designed to enhance glottal adduction and stabilize vocal fold vibration through partial nasal occlusion during phonation. Prior research (Radhakrishnan, 2022) demonstrated significant increases in Closed Quotient (CQ) and reductions in Jitter during NR humming, indicating improved vocal efficiency and stability. The present mixed-methods study expands on those findings by examining consonant-specific differences across /m/, /n/, and /ŋ/, and by incorporating qualitative insights from singers and voice teachers regarding pedagogical and perceptual outcomes.

Methods:
Electroglottographic (EGG) and acoustic data were collected from 24 female participants (aged 20–26 years) performing the NR technique on /m/, /n/, and /ŋ/. EGG signals were recorded using an EG2-PCX2 system and analyzed with EFxHist software to extract CQ and Jitter values. Shapiro–Wilk tests confirmed normality, and repeated-measures ANOVA with Bonferroni corrections and Cohen’s d were applied for within-subject comparisons. In parallel, 44 singers and voice teachers completed a 20-item survey assessing perceived benefits, limitations, and instructional considerations related to NR use in studio and clinical settings.

Results:
CQ was significantly higher for NR-/m/ (44.75%) and NR-/n/ (44.45%) compared to NR-/ŋ/ (37.72%) (p < .001, η² = .93). Jitter was significantly lower for /m/ (0.23%) and /n/ (0.22%) than for /ŋ/ (0.30%) (p < .001, η² = .32), suggesting greater phonatory stability in bilabial and alveolar contexts. Qualitative findings revealed consistent perceptions of improved resonance, efficiency, and vocal fold closure, alongside reduced effort and strain. Respondents described NR as simple, effective, and equipment-free, though some reported challenges with maintaining the appropriate nasal seal and avoiding over-nasality.

Conclusion:
The NR Technique effectively enhances glottal closure and phonatory stability, with measurable differences across nasal consonants linked to articulatory and aerodynamic factors. Its positive reception among performers and educators underscores its potential as a practical, evidence-based tool for both therapeutic and pedagogical voice habilitation. The immediacy of sensory feedback makes it especially valuable for promoting efficient and resonant voice production.