As many of you know, occlusion plays a big part in my approach to training the voice. The back pressure produced by voiced occlusives, like liptrills and voiced fricatives like [v], [z], voiced th, etc, create an inertial load above the glottis, which simplistically put, creates the conditions for a better balance of pressure/flow. The occlusives prevent and/or correct excessive medial pressure by assuring adequate trans-glottal flow and thereby encouraging continuous diaphragmatic rise. These are the basic condictions needed for adequate breath support. The rest has to do with management of the the ribcage to prevent excessive pressure and engagement of the core musculature to prevent diaphragmatic collapse in the event of higher sub-glottic pressure conditions.
The benefits of occlusion can and should go beyond voiced occlusives. In my teaching and singing I have observed that the proper production of consonants will have a beneficial effect on the succeeding vowel. This reminds me of an advice given to me by the late, great coach, Glenn Parker: “The strength of the consonants should be relative to the strength of the tone”. This was always helpful. This concept has become clearer in my mind through my work with occlusives.
I observe two tendencies among students: 1) the tendency to overpressurize and explode consonants in the name of diction and 2) the tendency to avoid the natural pressure of consonants in fear that the pressure will cause unwanted tension. Both are ill-advised. There is a middle ground, which provides clear articulation of the consonants, properly pressurized with respect to the support needs of the succeding vowel. The overpressurizing of consonants will create tension in the following vowel because the tone will be out of balanced. Hence the diction itself is lost since good diction is not only a matter of consonants but also (if not primarily) a matter of excellent tone production. In the case of underpressurizing the consonants (i.e. avoiding them), the following tone will have to be adjusted to become viable. This will require extra work from the support system and an uncessary readjustment from the glottis for each consonant and its succeding vowel. The voice will feel very insecure from note to note and a true legato will be lost. Indeed the legato effect is created not by continual flow but by a continual pressure/flow balance, which must be maintained in the production of consonants as well.
I used to follow the model of some of my past teachers who advocated avoiding consonants in the high range particularly for women. There is a practical aspect to ths advice. Most singers do not have a glottal posture in the high range that would make consonants easy to articulate. A good consonants requires pressure/flow balance and the inablility to sing easy consonants in the high range is a sign of pressed phonation to a degree. Whe the student has not yet accomplished a balanced fold posture in the high range, avoiding consonants can provide an easier result at the top, but that should be a short term measure. The top voice should be developed to produce consonants easily. Indeed consonants are not necessarily limited by formant resonance like vowels are. It fascinated me when I was in school that the singer with the best diction was a coloratura voice teacher, given the fact that she was modifying vowels most of the time by necessity. Her top voice was as fully developed (no flute voice production in her top) as her middle. She sang strong, flowing consonants even when vowels had to be modified. When consonants are well-produced, the modified vowel is understood as the desired vowel in context. Indeed her fine diction was as much a product of her consonants as it was of her balanced phonation on vowels. And in truth, they are not mutually exclusive. The point I hope to make here is that a balanced tone on a vowel in fact depends on the balanced consonant that precedes