Gallena SJK et al. – This study was conducted to understand formant conditions that shift listeners' perception of gender from male to “not–male,” individual and combined vowel FFs were incrementally raised, whereas Fο was held constant at a gender–ambiguous level in male–to–female transgender women. It was observed that voice was convincingly perceived as not male, high F1 frequency vowels, and raise in FFs for all vowels resulted in increase in perception of voice of femininity beyond that of raising Fο alone.