Is it necessary to be concerned about what vowels a singer must use to produce a Singer’s Formant?
The Singer’s Formant has no relation to the effect of vowels on resonance. This is because the Singer’s Formant is produced in an area of the vocal mechanism that is removed from the critical vowel resonance area.
Singer’s Formant is produced in the aryepiglottic area which is directly above the vocal folds and directly below the pharyngeal and buccal areas which produce the vowels.
There is no doubt about the importance of vowel resonance and its effect on vocal tone. Vowels must be chosen such that they produce maximum resonance of the phonated tone but these resonance ranges are below the Singer’s Formant range and for this reason vowel tuning, even if perfectly produced does not guarantee production of Singer’s Formant. And the corollary is also true; when a Singer’s Formant is produced it will not be affected by the vowel that is chosen even if that vowel is not tuned to achieve maximum vowel resonance.
In short, the quality of the vocal tone is arranged around the production of accurate vowel tuning, but the Singer’s Formant is developed by adjustments lower in the vocal mechanism, that is, in the aryepiglottic space.