Which came first, the chicken or the egg? A quandary that no-one seems to be able to figure out. However, for us as singers, thankfully the question of which is first, vocal cords or vowels, is one that we can answer!
The vocal cords are our first concern on a couple of levels:
So, what is going on with the cords is the focus. The registration – balance amongst muscles in the larynx responsible for cordal adjustment – is primary with all other adjustments made as automatic response flowing from the registrational adjustments. If the registration is disturbed, then all else becomes disturbed, like a ripple effect. If the registration is improved, then all else becomes improved.
Of course, during training there is use of vowel, repetition of a consonant, or focus on tongue position so as to assist in re-education and healing of muscles. But, this in service to freeing the registrational muscles so that they can do their jobs allowing all else to work better.
The registration is primary, but all the parts are interconnected and interdependent!